{"title":"Keystone Formula","description":"\u003cdiv style=\"text-align: center;\"\u003e\n\u003cdiv style=\"display: inline-block; max-width: 900px; text-align: left;\"\u003eFountain pen ink manufactured at our workshop, Keystone Formula inks are built with traditional water-soluble dye colorants to produce a broad spectrum of hues.\u003c\/div\u003e\n\u003c\/div\u003e","products":[{"product_id":"boiler-steam","title":"Boiler Steam","description":"\u003cp style=\"text-align: right;\"\u003eMove the iron horse.\u003c\/p\u003e\n\u003cp\u003eBoiler Steam is part of the Keystone Formula fountain pen ink line, our traditional dye-colorant ink. \u003cspan\u003eThe 50mL volume will provide approximately 62 standard converter refills assuming a 0.8mL draw.\u003c\/span\u003e\u003cspan\u003e Our ink swatch is produced with a cotton swab on Tomoe River paper.\u003c\/span\u003e\u003c\/p\u003e","brand":"Fountain Pen Ink","offers":[{"title":"50mL Glass Bottle","offer_id":47365916852466,"sku":"PN100533","price":17.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1237\/1088\/files\/Boiler_Steam_4eea0ace-f3f7-4e48-96b7-c7ce0af2436f.jpg?v=1750435394"},{"product_id":"tesla-coil","title":"Tesla Coil","description":"\u003cp\u003e\u003cmeta charset=\"utf-8\"\u003eOne of our most popular inks, Tesla Coil is a rich cobalt blue color that will produce a iridescent magenta sheening effect when saturated on high-quality papers like Tomoe River and Rhodia. The pictured writing sample is made on 68 gsm Tomoe River paper with a cotton swab and medium nib. \u003cstrong\u003eThis colorant will produce a pure cobalt blue on sorbent papers.\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan\u003e\u003cem\u003e*Fountain pen ink sheen properties are best expressed when the ink is saturated on slightly hydrophobic papers like Tomoe River or Rhodia. Get the best results with a wet line. \u003cmeta charset=\"utf-8\"\u003e \u003cstrong\u003eVisible coloring will vary drastically by paper type and saturation\u003c\/strong\u003e.\u003c\/em\u003e\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003eTesla Coil is part of the Keystone Formula fountain pen ink line, our traditional dye-colorant ink. \u003cspan\u003eThe 90mL volume will provide approximately 112 standard converter refills assuming a 0.8mL draw.\u003c\/span\u003e\u003cspan\u003e \u003cmeta charset=\"utf-8\"\u003eWe manufacture this ink in Pennsylvania with domestic and imported ingredients.\u003c\/span\u003e\u003cmeta charset=\"utf-8\"\u003e\u003c\/p\u003e","brand":"Fountain Pen Ink","offers":[{"title":"Default Title","offer_id":44524682051826,"sku":"PN100162","price":29.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1237\/1088\/files\/Tesla_Coil_4393c4ed-15e4-4905-85e2-471e89dc0834.jpg?v=1779376595"},{"product_id":"voltaic-arc","title":"Voltaic Arc","description":"\u003cp\u003e\u003cspan\u003eVoltaic is a vivid dark blue to blue-black that sparks with a rich merlot sheen in saturation for an alternating current of a finish.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003c\/strong\u003e\u003cem\u003e*Fountain pen ink sheen properties are best expressed when the ink is saturated on slightly hydrophobic papers like Tomoe River or Rhodia. Get the best results with a wet line. \u003cmeta charset=\"utf-8\"\u003e \u003cspan\u003e\u003cspan style=\"text-decoration: underline;\"\u003eVisible coloring will vary drastically by paper type and saturation\u003c\/span\u003e.\u003c\/span\u003e\u003c\/em\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan\u003ePart of the Keystone Formula fountain pen ink line, Voltaic Arc is built with \u003cmeta charset=\"utf-8\"\u003etraditional water-soluble dye colorants. Our ink color swatch is produced with a cotton swab on Tomoe River paper and writing sample with a German medium nib. \u003c\/span\u003e\u003cspan\u003eThe 50mL volume will provide approximately 62 standard converter refills assuming a 0.8mL draw. G\u003c\/span\u003elass bottles arrive prepared in our beautifully foiled Birmingham Pen Co. gift box.\u003c\/p\u003e","brand":"Fountain Pen Ink","offers":[{"title":"50mL Glass Bottle","offer_id":47365916721394,"sku":"PN100165","price":17.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1237\/1088\/files\/Voltaic_Arc_hiRes.jpg?v=1737127386"},{"product_id":"pitted-nickel","title":"Pitted Nickel","description":"\u003cp style=\"text-align: center;\"\u003e\u003cstrong\u003eGET ONE\u003cspan\u003e \u003c\/span\u003e\u003cspan style=\"color: rgb(231, 0, 0);\"\u003eFREE\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e bottle with Pitted Nickel in the \u003ca href=\"https:\/\/www.birminghampens.mom\/products\/tigers-eye-bundle\" title=\"Tiger's Eye Ink Bundle\"\u003e\u003cstrong\u003e\u003cspan style=\"color: rgb(90, 49, 244);\"\u003eTiger's Eye Ink Bundle\u003c\/span\u003e\u003c\/strong\u003e\u003c\/a\u003e.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003ePitted Nickel is part of the Keystone Formula fountain pen ink line, our traditional dye-colorant ink. \u003cmeta charset=\"UTF-8\"\u003e\u003cspan\u003eThe 50mL volume will provide approximately 62 standard converter refills assuming a 0.8mL draw.\u003c\/span\u003e\u003cspan\u003e Our ink swatch is produced with a cotton swab on Tomoe River paper. \u003cmeta charset=\"utf-8\"\u003eWe manufacture this ink in Pennsylvania with domestic and imported ingredients.\u003c\/span\u003e\u003c\/p\u003e","brand":"Fountain Pen Ink","offers":[{"title":"50mL Glass Bottle","offer_id":48251178516722,"sku":"PN100194","price":17.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1237\/1088\/files\/Pitted_Nickel_b03fe87c-e176-43f4-8b00-b6cf8953776b.jpg?v=1763749217"},{"product_id":"ohio-river","title":"Ohio River","description":"\u003cp style=\"text-align: right;\"\u003e\u003cem\u003eOhio River starts at the point.\u003c\/em\u003e\u003c\/p\u003e\n\u003cp\u003eOhio River is part of the Keystone Formula fountain pen ink line, our traditional dye-colorant ink. \u003cspan\u003eThe 50mL volume will provide approximately 62 standard converter refills assuming a 0.8mL draw.\u003c\/span\u003e\u003cspan\u003e Our ink swatch is produced with a cotton swab on Tomoe River paper. \u003cmeta charset=\"utf-8\"\u003eWe manufacture this ink in Pennsylvania with domestic and imported ingredients.\u003c\/span\u003e\u003cspan\u003e\u003c\/span\u003e\u003c\/p\u003e","brand":"Fountain Pen Ink","offers":[{"title":"50mL Glass Bottle","offer_id":47365916557554,"sku":"PN100200","price":17.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1237\/1088\/files\/Ohio_River.jpg?v=1774542380"},{"product_id":"angelfish","title":"Angelfish","description":"\u003cp\u003e\u003cspan\u003eAngelfish is a vivid oceanic blue that glows with merlot sheen in saturation on slightly hydrophobic fountain pen friendly papers.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cem\u003eTo achieve the secondary merlot color sheening property in \u003cmeta charset=\"utf-8\"\u003eAngelfish, it generally requires a well saturated stroke on fountain pen friendly paper. \u003c\/em\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan\u003ePart of the Keystone Formula fountain pen ink line, \u003cmeta charset=\"utf-8\"\u003eAngelfish is built with traditional dye-colorants. Our ink color swatch and writing samples are produced on Tomoe River paper with a cotton swab and medium point grade nib. \u003c\/span\u003e\u003cspan\u003eThe 50mL volume will provide approximately 62 standard converter refills assuming a 0.8mL draw. G\u003c\/span\u003elass bottles arrive prepared in our beautifully foiled Birmingham Pen Co. gift box. \u003cmeta charset=\"utf-8\"\u003e\u003cspan\u003eWe manufacture this ink in Pennsylvania with domestic and imported ingredients.\u003c\/span\u003e\u003c\/p\u003e","brand":"Fountain Pen Ink","offers":[{"title":"50mL Glass Bottle","offer_id":47901462528242,"sku":"PN100335","price":17.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1237\/1088\/files\/Angelfish_07913a8a-fa4f-465a-b5be-cfdbd5ee93af.jpg?v=1773240323"},{"product_id":"heron","title":"Heron","description":"\u003cp style=\"text-align: center;\"\u003e\u003cstrong\u003eGET ONE\u003cspan\u003e \u003c\/span\u003e\u003cspan style=\"color: rgb(231, 0, 0);\"\u003eFREE\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e bottle with Heron in the \u003ca title=\"Tiger's Eye Ink Bundle\" href=\"https:\/\/www.birminghampens.mom\/products\/tigers-eye-bundle\"\u003e\u003cstrong\u003e\u003cspan style=\"color: rgb(90, 49, 244);\"\u003eTiger's Eye Ink Bundle\u003c\/span\u003e\u003c\/strong\u003e\u003c\/a\u003e.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003eHeron is part of the Keystone Formula fountain pen ink line, our traditional dye-colorant ink. \u003cmeta charset=\"UTF-8\"\u003e\u003cspan\u003eThe 50mL volume will provide approximately 62 standard converter refills assuming a 0.8mL draw.\u003c\/span\u003e\u003cspan\u003e Our ink swatch is produced with a cotton swab on Tomoe River paper. \u003cmeta charset=\"utf-8\"\u003eWe manufacture this ink in Pennsylvania with domestic and imported ingredients.\u003c\/span\u003e\u003c\/p\u003e","brand":"Fountain Pen Ink","offers":[{"title":"50mL Glass Bottle","offer_id":48251173175538,"sku":"PN100463","price":17.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1237\/1088\/files\/Heron_c1294517-0a8a-4383-a756-630d8acc94be.jpg?v=1763748859"},{"product_id":"emerald-fusion","title":"Emerald Fusion","description":"\u003cp style=\"text-align: right;\"\u003e\u003cem\u003eGo nuclear. \u003c\/em\u003e\u003c\/p\u003e\n\u003cp\u003eEmerald Fusion is packed with colorant and will produce a striking green sheen on common fountain pen friendly papers. This highly saturated hue may write on the dry side in some pens - get the best performance in a well flowing writer equipped with a medium point grade nib or broader. Part of our \u003cmeta charset=\"utf-8\"\u003etraditional dye-colorant Keystone Formula ink line, t\u003cspan\u003ehe 90mL minimum volume will provide approximately 112 standard converter refills assuming a 0.8mL draw. \u003c\/span\u003e\u003cspan\u003eOur ink swatch is produced with a cotton swab on Tomoe River paper. \u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003ePrepare for an INTENSE green sheen on fountain-pen-friendly papers like Tomoe River and Rhodia. \u003cmeta charset=\"utf-8\"\u003e\u003cspan\u003eWe manufacture this ink in Pennsylvania with domestic and imported ingredients.\u003c\/span\u003e\u003c\/p\u003e","brand":"Fountain Pen Ink","offers":[{"title":"90mL Glass Bottle","offer_id":47365915738354,"sku":"PN100639","price":29.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1237\/1088\/files\/Emerald_Fusion_e1baaa27-5210-4e5c-8e51-fc432c1055c4.jpg?v=1779376506"},{"product_id":"burlywood","title":"Burlywood","description":"\u003cp style=\"text-align: left;\"\u003eKnots of character. \u003c\/p\u003e\n\u003cp\u003eBurlywood is part of the Keystone Formula fountain pen ink line, our traditional dye-colorant ink. \u003cspan\u003eThe 50mL volume will provide approximately 62 standard converter refills assuming a 0.8mL draw.\u003c\/span\u003e\u003cspan\u003e Our ink swatch is produced with a cotton swab on Tomoe River paper. We manufacture this ink in Pennsylvania with domestic and imported ingredients.\u003c\/span\u003e\u003cmeta charset=\"utf-8\"\u003e\u003c\/p\u003e","brand":"Fountain Pen Ink","offers":[{"title":"50mL Glass Bottle","offer_id":47365915246834,"sku":"PN100641","price":17.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1237\/1088\/files\/Burlywood_b9a808fb-9293-4be1-ab72-3b7bdb6037c9.jpg?v=1774542241"},{"product_id":"tiger-lily","title":"Tiger Lily","description":"\u003cp style=\"text-align: right;\"\u003e\u003cem\u003eSubtly ferocious.\u003c\/em\u003e\u003c\/p\u003e\n\u003cp\u003eTiger Lily is part of the Keystone Formula fountain pen ink line, our traditional dye-colorant ink. \u003cmeta charset=\"UTF-8\"\u003e\u003cspan\u003eThe 100mL volume will provide approximately 125 standard converter refills assuming a 0.8mL draw. \u003cmeta charset=\"utf-8\"\u003eWe manufacture this ink in Pennsylvania with domestic and imported ingredients.\u003c\/span\u003e\u003cmeta charset=\"utf-8\"\u003e\u003c\/p\u003e","brand":"Fountain Pen Ink","offers":[{"title":"100mL Glass Bottle","offer_id":47346182193394,"sku":"PN100680","price":25.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1237\/1088\/files\/Tiger_Lily_79cf144b-8d13-40ff-943b-9e03038d5957.jpg?v=1774542483"},{"product_id":"aqueduct","title":"Aqueduct","description":"\u003cp style=\"text-align: center;\"\u003e\u003cmeta charset=\"utf-8\"\u003e\u003cstrong\u003eGET ONE\u003cspan\u003e \u003c\/span\u003e\u003cspan style=\"color: rgb(231, 0, 0);\"\u003eFREE\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e bottle with Aqueduct in the \u003ca href=\"https:\/\/www.birminghampens.mom\/products\/firebox-ink-bundle\" title=\"Angelfish\"\u003e\u003cstrong\u003e\u003cspan style=\"color: rgb(90, 49, 244);\"\u003eFirebox Ink Bundle\u003c\/span\u003e\u003c\/strong\u003e\u003c\/a\u003e. \u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003eAqueduct is part of the Keystone Formula fountain pen ink line, our traditional dye-colorant ink. The generous 100mL volume will provide approximately 125 standard converter refills assuming a 0.8mL draw. \u003cmeta charset=\"utf-8\"\u003e\u003cspan\u003eWe manufacture this ink in Pennsylvania with domestic and imported ingredients.\u003c\/span\u003e\u003c\/p\u003e","brand":"Fountain Pen Ink","offers":[{"title":"50mL Glass Bottle","offer_id":47678538645746,"sku":"PN100690","price":17.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1237\/1088\/files\/Aqueduct_4f4e00bb-14d2-4455-b25b-c8c1e00b2704.jpg?v=1761769032"},{"product_id":"iron-ore","title":"Iron Ore","description":"\u003cp style=\"text-align: center;\"\u003e\u003cmeta charset=\"utf-8\"\u003e\u003cstrong\u003eGET ONE\u003cspan\u003e \u003c\/span\u003e\u003cspan style=\"color: rgb(231, 0, 0);\"\u003eFREE\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e bottle with Iron Ore in the \u003ca title=\"Angelfish\" href=\"https:\/\/www.birminghampens.mom\/products\/firebox-ink-bundle\"\u003e\u003cstrong\u003e\u003cspan style=\"color: rgb(90, 49, 244);\"\u003eFirebox Ink Bundle\u003c\/span\u003e\u003c\/strong\u003e\u003c\/a\u003e. \u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003eIron Ore is part of the Keystone Formula fountain pen ink line, our traditional dye-colorant ink. \u003cspan\u003eThe 50mL volume will provide approximately 62 standard converter refills assuming a 0.8mL draw.\u003c\/span\u003e\u003cspan\u003e Our ink swatch is produced with a cotton swab on Tomoe River paper. \u003cmeta charset=\"utf-8\"\u003eWe manufacture this ink in Pennsylvania with domestic and imported ingredients.\u003c\/span\u003e\u003c\/p\u003e","brand":"Fountain Pen Ink","offers":[{"title":"50mL Glass Bottle","offer_id":47365913837810,"sku":"PN100874","price":17.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1237\/1088\/files\/Iron_Ore_25394a42-be87-4add-b4c7-f75734ed2a56.jpg?v=1763495330"},{"product_id":"interstellar-bronze","title":"Interstellar Bronze","description":"\u003cp\u003eBending spacetime and testing the limits of rich colorant saturation, Interstellar Bronze is a mesmerizing fusion of cosmic curiosity. This ultra-saturated hue shows a rich bronze-brown base that's overwhelmed with galactic fluorescent green sheen on slightly hydrophobic fountain-pen-friendly papers. Curiously purple-hued in the bottle, Interstellar Bronze is one-of-a-kind in any ink collection. \u003c\/p\u003e\n\u003cp\u003eSince this is an extremely saturated ink, some pens may operate on the dry side. Easily make the ink perform wetter by reducing viscosity to taste, blending with \u003ca title=\"Dilution Solution\" href=\"https:\/\/www.birminghampens.mom\/products\/dilution-solution\"\u003eDilution Solution\u003c\/a\u003e or another Birmingham Pen Company ink. Visual properties will gradually alter with dilution, varying by diluent. Frequent pen cleaning is suggested and could require extra effort, but the dye colorants are entirely water-soluble. \u003cmeta charset=\"utf-8\"\u003eThis supersaturated hue performs best with broad point-grade nibs or thicker. We recommend a full pen cleaning every 4-5 days using this ultra saturated ink. \u003c\/p\u003e\n\u003cp\u003eInterstellar Bronze is part of the Keystone Formula fountain pen ink line, our traditional dye-colorant ink. \u003cmeta charset=\"UTF-8\"\u003e\u003cspan\u003eThe 90mL minimum volume will provide approximately 112 standard converter refills assuming a 0.8mL draw.\u003c\/span\u003e\u003cspan\u003e Our ink swatch is produced with a cotton swab on Tomoe River paper. \u003cmeta charset=\"utf-8\"\u003eWe manufacture this ink in Pennsylvania with domestic and imported ingredients.\u003c\/span\u003e\u003c\/p\u003e","brand":"Fountain Pen Ink","offers":[{"title":"90mL Glass Bottle","offer_id":47365908955378,"sku":"PN100707","price":29.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1237\/1088\/files\/Interstellar_Bronze_97fd45be-7543-4952-a57c-6e364cff7407.jpg?v=1779376567"},{"product_id":"firebox","title":"Firebox","description":"\u003cp style=\"text-align: center;\"\u003e\u003cmeta charset=\"utf-8\"\u003e\u003cstrong\u003eGET ONE\u003cspan\u003e \u003c\/span\u003e\u003cspan style=\"color: rgb(231, 0, 0);\"\u003eFREE\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e bottle with Firebox in the \u003ca href=\"https:\/\/www.birminghampens.mom\/products\/firebox-ink-bundle\" title=\"Angelfish\"\u003e\u003cstrong\u003e\u003cspan style=\"color: rgb(90, 49, 244);\"\u003eFirebox Ink Bundle\u003c\/span\u003e\u003c\/strong\u003e\u003c\/a\u003e. \u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003eFirebox is part of the Keystone Formula fountain pen ink line, our traditional dye-colorant ink. \u003cspan\u003eThe 50mL volume will provide approximately 62 standard converter refills assuming a 0.8mL draw.\u003c\/span\u003e\u003cspan\u003e Our ink swatch is produced with a cotton swab on Tomoe River paper. \u003cmeta charset=\"utf-8\"\u003eWe manufacture this ink in Pennsylvania with domestic and imported ingredients.\u003c\/span\u003e\u003cbr\u003e\u003c\/p\u003e","brand":"Fountain Pen Ink","offers":[{"title":"50mL Glass Bottle","offer_id":47347669205234,"sku":"PN100708","price":17.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1237\/1088\/files\/Firebox_5379b94a-fae9-4435-8598-0d7abfbf9cad.jpg?v=1774542274"},{"product_id":"extradimensional-umber","title":"Extradimensional Umber","description":"\u003cp\u003eAn ultra-saturated quasi-sheening sepia, Extradimensional Umber bends the color wheel. With a robust sepia base and a hint of green sheen at the right angle, stretching to sandy caramel on a speedier stroke, this hue will surely be one of the most mind-bending in your collection. \u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eWARNING\u003c\/strong\u003e: Photographing the character in this ink is difficult. I've done my best to capture the extradimensional nuance, but you're bound to find something new as you play with stronger and weaker saturations on different papers in various lighting atmospheres. \u003cmeta charset=\"utf-8\"\u003e\u003cspan\u003eOur ink swatch is produced with a cotton swab on Tomoe River paper. \u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003eSince this is an extremely saturated ink, some pens may operate on the dry side and extra effort may be required in cleaning. Extradimensional Umber is part of the Keystone Formula fountain pen ink line, built with water soluble dye-colorants. \u003cspan\u003eThe 90mL volume will provide approximately 112 standard converter refills assuming a 0.8mL draw.\u003c\/span\u003e\u003cspan\u003e \u003c\/span\u003e\u003c\/p\u003e","brand":"Fountain Pen Ink","offers":[{"title":"Default Title","offer_id":44667640348914,"sku":"PN100718","price":29.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1237\/1088\/files\/Extradimensional_Umber_e0e276b2-fef2-4596-bafd-cd3b209e0a93.jpg?v=1779376538"},{"product_id":"phoenix","title":"Phoenix","description":"\u003cp\u003ePhoenix blazes with an energetic spectrum, flowing from a luminous yellow to a smoldering orange when highly saturated on hydrophobic papers. \u003c\/p\u003e\n\u003cp\u003e\u003cspan\u003eThe 50mL volume will provide approximately 62 standard converter refills assuming a 0.8mL draw. Our ink swatch is produced with a cotton swab on Tomoe River paper.\u003c\/span\u003e\u003c\/p\u003e","brand":"Fountain Pen Ink","offers":[{"title":"50mL Glass Bottle","offer_id":47367806812402,"sku":"PN100873","price":17.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1237\/1088\/files\/Phoenix_d09e5e13-2b76-4809-9c97-b6cf1886f3a3.jpg?v=1750281287"},{"product_id":"mountain-thistle","title":"Mountain Thistle","description":"\u003cp\u003eMountain Thistle is a soft highland heather with complexity in saturation on fountain pen friendly papers. Color shifts from a soft lavender at dusk to a muted violet.\u003c\/p\u003e\n\u003cp\u003eMountain Thistle is part of the Keystone Formula fountain pen ink line, our traditional dye-colorant ink. The 50mL volume will provide approximately 60 standard converter refills assuming a 0.8mL draw. \u003cmeta charset=\"utf-8\"\u003e\u003cspan\u003eWe manufacture this ink in Pennsylvania with domestic and imported ingredients.\u003c\/span\u003e\u003c\/p\u003e","brand":"Fountain Pen Ink","offers":[{"title":"50mL Glass Bottle","offer_id":49110852894962,"sku":"PN100727","price":17.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1237\/1088\/files\/Mountain_Thistle_fbd4817b-e333-4c8a-af4c-1879662809e7.jpg?v=1774542350"},{"product_id":"byzantium","title":"Byzantium","description":"\u003cp style=\"text-align: center;\"\u003e\u003cstrong\u003eGET ONE\u003cspan\u003e \u003c\/span\u003e\u003cspan style=\"color: rgb(231, 0, 0);\"\u003eFREE\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e bottle of Byzantium in the \u003ca href=\"https:\/\/www.birminghampens.mom\/products\/tigers-eye-bundle\" title=\"Tiger's Eye Ink Bundle\"\u003e\u003cstrong\u003e\u003cspan style=\"color: rgb(90, 49, 244);\"\u003eTiger's Eye Ink Bundle\u003c\/span\u003e\u003c\/strong\u003e\u003c\/a\u003e.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003eByzantium is part of the Keystone Formula fountain pen ink line, our traditional dye-colorant ink. \u003cmeta charset=\"UTF-8\"\u003e\u003cspan\u003eThe 50mL volume will provide approximately 62 standard converter refills assuming a 0.8mL draw.\u003c\/span\u003e\u003cspan\u003e Our ink swatch is produced with a cotton swab on Tomoe River paper. \u003cmeta charset=\"utf-8\"\u003eWe manufacture this ink in Pennsylvania with domestic and imported ingredients.\u003c\/span\u003e\u003c\/p\u003e","brand":"Fountain Pen Ink","offers":[{"title":"Default Title","offer_id":44901443404018,"sku":"PN100730","price":17.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1237\/1088\/files\/Byzantium.jpg?v=1763748990"},{"product_id":"saltmarsh","title":"Saltmarsh","description":"\u003cp\u003e\u003cspan data-sheets-userformat='{\"2\":33567427,\"3\":{\"1\":0},\"4\":{\"1\":2,\"2\":16777215},\"9\":1,\"10\":2,\"12\":0,\"15\":\"Roboto\",\"16\":12,\"28\":1}' data-sheets-value='{\"1\":2,\"2\":\"Saltmarsh\"}' data-sheets-root=\"1\"\u003eSaltmarsh is one unique hue! Depending on the type of light in proximity to the ink it can change from a marshy green all the way to a light coffee brown. In our experience the ink shifts to the coffee tone in daylight, and back to the green tone in most (\u003cem\u003ethough not all\u003c\/em\u003e) indoor lighting.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan data-sheets-userformat='{\"2\":33567427,\"3\":{\"1\":0},\"4\":{\"1\":2,\"2\":16777215},\"9\":1,\"10\":2,\"12\":0,\"15\":\"Roboto\",\"16\":12,\"28\":1}' data-sheets-value='{\"1\":2,\"2\":\"Saltmarsh\"}' data-sheets-root=\"1\"\u003eSaltmarsh\u003c\/span\u003e is part of the Keystone Formula fountain pen ink line, our traditional dye-colorant ink. \u003cmeta charset=\"UTF-8\"\u003e\u003cspan\u003eThe 50mL volume will provide approximately 62 standard converter refills assuming a 0.8mL draw.\u003c\/span\u003e\u003cspan\u003e Our ink swatch is produced with a cotton swab on Tomoe River paper. \u003cmeta charset=\"utf-8\"\u003eWe manufacture this ink in Pennsylvania with domestic and imported ingredients.\u003c\/span\u003e\u003c\/p\u003e","brand":"Fountain Pen Ink","offers":[{"title":"50mL Glass Bottle","offer_id":47483452424434,"sku":"PN100741","price":17.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1237\/1088\/files\/Saltmarsh_25dfaf3a-ee95-4de0-860f-bfb45ed4719b.jpg?v=1774542409"},{"product_id":"hydrothermal-spring","title":"Hydrothermal Spring","description":"\u003cp\u003e\u003cspan\u003eHydrothermal Spring is built with a moderate colorant saturation that produces shades that shift from a rich aquatic teal to a soft navy in saturation.\u003cspan class=\"Apple-converted-space\"\u003e \u003c\/span\u003e\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan data-sheets-root=\"1\" data-sheets-value='{\"1\":2,\"2\":\"Hydrothermal Spring\"}' data-sheets-userformat='{\"2\":33567427,\"3\":{\"1\":0},\"4\":{\"1\":2,\"2\":14743546},\"9\":1,\"10\":2,\"12\":0,\"15\":\"Roboto\",\"16\":12,\"28\":1}'\u003eHydrothermal Spring\u003c\/span\u003e is part of the Keystone Formula fountain pen ink line, our traditional dye-colorant ink. \u003cspan\u003eThe 50mL volume will provide approximately 62 standard converter refills assuming a 0.8mL draw.\u003c\/span\u003e\u003cspan\u003e Our ink swatch is produced with a cotton swab on Tomoe River paper. \u003cmeta charset=\"utf-8\"\u003eWe manufacture this ink in Pennsylvania with domestic and imported ingredients.\u003c\/span\u003e\u003c\/p\u003e","brand":"Fountain Pen Ink","offers":[{"title":"50mL Glass Bottle","offer_id":47365908300018,"sku":"PN100742","price":17.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1237\/1088\/files\/Hydrothermal_Spring_29eabd0d-551a-4a9b-a472-ce3ba5337391.jpg?v=1747409091"},{"product_id":"sugar-kelp","title":"Sugar Kelp","description":"\u003cp\u003e\u003cspan data-sheets-root=\"1\" data-sheets-value='{\"1\":2,\"2\":\"Sugar Kelp\"}' data-sheets-userformat='{\"2\":33567427,\"3\":{\"1\":0},\"4\":{\"1\":2,\"2\":14743546},\"9\":1,\"10\":2,\"12\":0,\"15\":\"Roboto\",\"16\":12,\"28\":1}'\u003eDive deep with Sugar Kelp to discover a variety of nuanced organic complexities.  Varying by saturation and paper type, this hue can range from a lighter citron to a shaded olive. \u003cspan\u003eThe 50mL volume will provide approximately 62 standard converter refills assuming a 0.8mL draw.\u003c\/span\u003e\u003c\/span\u003e\u003cspan\u003e Our ink swatch is produced with a cotton swab on Tomoe River paper. \u003cmeta charset=\"utf-8\"\u003eWe manufacture this ink in Pennsylvania with domestic and imported ingredients.\u003c\/span\u003e\u003c\/p\u003e","brand":"Fountain Pen Ink","offers":[{"title":"50mL Glass Bottle","offer_id":47860381581554,"sku":"PN100744","price":17.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1237\/1088\/files\/Sugar_Kelp_088ab16c-9e9b-4c76-8d7c-553131d7b01c.jpg?v=1774542434"},{"product_id":"tigers-eye","title":"Tiger's Eye","description":"\u003cp\u003e\u003cmeta charset=\"utf-8\"\u003e\u003cspan\u003e\u003cspan data-sheets-root=\"1\"\u003eTiger's Eye\u003c\/span\u003e is part of the Keystone Formula fountain pen ink line, our traditional dye-colorant ink. \u003cmeta charset=\"UTF-8\"\u003eThe 50mL volume will provide approximately 62 standard converter refills assuming a 0.8mL draw. Our ink swatch is produced with a cotton swab on Tomoe River paper. \u003cmeta charset=\"utf-8\"\u003eWe manufacture this ink in Pennsylvania with domestic and imported ingredients.\u003c\/span\u003e\u003c\/p\u003e","brand":"Fountain Pen Ink","offers":[{"title":"50mL Glass Bottle","offer_id":48251172487410,"sku":"PN100855","price":17.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1237\/1088\/files\/Tigers_Eye_a9698d2f-7c12-4290-93e2-c4927f4215eb.jpg?v=1763748688"},{"product_id":"suncatcher","title":"Suncatcher","description":"\u003cp style=\"text-align: right;\"\u003eLight’s favorite souvenir.\u003c\/p\u003e\n\u003cp\u003eSuncatcher is part of the Keystone Formula fountain pen ink line, our traditional dye-colorant ink. \u003cspan\u003eThe 50mL volume will provide approximately 62 standard converter refills assuming a 0.8mL draw.\u003c\/span\u003e\u003cspan\u003e Our ink swatch is produced with a cotton swab on Tomoe River paper.\u003c\/span\u003e\u003c\/p\u003e","brand":"Fountain Pen Ink","offers":[{"title":"50mL Glass Bottle","offer_id":47443705528562,"sku":"PN100915","price":17.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1237\/1088\/files\/Suncatcher_6116b606-e495-4e16-bb85-622f3951d303.jpg?v=1774542458"}],"url":"https:\/\/www.birminghampens.mom\/collections\/keystone-formula-inks.oembed?page=3","provider":"Birmingham Pen Company","version":"1.0","type":"link"}