{"product_id":"copper-carbonate-50-pounds-rmcopcar","title":"Copper Carbonate","description":"\u003cp\u003e\u003cstrong\u003eGives you greens in an electric kiln and copper reds in a gas kiln. One of the most popular glaze colorants.\u003c\/strong\u003e\u003c\/p\u003e\n\u003cdiv class=\"rm-testing-statement\" style=\"border:2px solid #8a5a00;border-radius:6px;padding:12px 16px;margin:16px 0;background:#fdf6e3;\"\u003e\u003cp style=\"margin:0;\"\u003e\u003cstrong\u003eYou must test before you use it, at any scale.\u003c\/strong\u003e Raw materials, mined or man-made, are not consistent. Color, strength, particle size and chemistry can change from one bag to the next and from one supplier to another, even when the name on the bag stays the same. Before you use this material in a glaze, slip or clay body of any size, mix a small test batch, fire it on your own clay in your own kiln, and check the results.\u003c\/p\u003e\u003c\/div\u003e\n\u003ch3\u003eWhat it is\u003c\/h3\u003e\n\u003cp\u003eA light green powder you mix into a glaze to give it color. In an electric kiln it makes greens, from pale to deep forest green. In a gas kiln fired \"in reduction\" (with less oxygen), a small amount can turn a glaze copper red.\u003c\/p\u003e\n\u003ch3\u003eGetting started\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003eAdd it to a clear or white base glaze. 2% is a good start: 2 grams of copper carbonate for every 100 grams of dry glaze.\u003c\/li\u003e\n\u003cli\u003e1 to 2% gives light green, 3 to 5% medium to deep green. Above about 5% it can turn metallic or black and make the glaze run.\u003c\/li\u003e\n\u003cli\u003eAfter mixing, pour the wet glaze through an 80-mesh sieve so the color comes out even, not streaky.\u003c\/li\u003e\n\u003cli\u003eFire a test tile before you glaze a whole batch.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3\u003eFor glaze formulators\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003eBasic copper carbonate, CuCO₃·Cu(OH)₂. About 72% CuO by weight; LOI about 28%.\u003c\/li\u003e\n\u003cli\u003eTo swap for black copper oxide: 1 part CuO ≈ 1.4 parts copper carbonate.\u003c\/li\u003e\n\u003cli\u003eFiner than copper oxide, so less specking. The gas it releases while firing can add to pinholing in thick coats.\u003c\/li\u003e\n\u003cli\u003eHigh-alkali and barium bases push copper toward turquoise and blue; calcium and boron bases give greens.\u003c\/li\u003e\n\u003cli\u003eCopper reds: usually 0.3 to 0.5% with about 1% tin oxide, fired in reduction. At high temperatures copper can vaporize and stain nearby pots and shelves.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3\u003eSafety\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003eHarmful if swallowed; don't breathe the dust. Wear a NIOSH-approved respirator (N95 or better) when weighing it dry. Wear gloves, and clean up with a wet sponge, not a broom.\u003c\/li\u003e\n\u003cli\u003eCopper can leach out of glazes on food surfaces, especially glossy, high-copper or under-fired glazes. For mugs, bowls and plates, use a stable, tested base glaze, and have the finished glaze lab-tested before you sell the work.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3\u003eSizes \u0026amp; pricing\u003c\/h3\u003e\n\u003ctable style=\"width:100%;max-width:520px;border-collapse:collapse;border:0;margin:0 0 14px;font-variant-numeric:tabular-nums;line-height:1.35;\"\u003e\n\u003cthead\u003e\u003ctr\u003e\n\u003cth style=\"padding:0 0 6px;border:0;border-bottom:2px solid #d9d0c4;background:transparent;font-size:12px;letter-spacing:.06em;text-transform:uppercase;font-weight:600;color:#6b6259;text-align:left;width:40%;\"\u003eSize\u003c\/th\u003e\n\u003cth style=\"padding:0 0 6px;border:0;border-bottom:2px solid #d9d0c4;background:transparent;font-size:12px;letter-spacing:.06em;text-transform:uppercase;font-weight:600;color:#6b6259;text-align:right;padding-left:12px;\"\u003ePrice\u003c\/th\u003e\n\u003cth style=\"padding:0 0 6px;border:0;border-bottom:2px solid #d9d0c4;background:transparent;font-size:12px;letter-spacing:.06em;text-transform:uppercase;font-weight:600;color:#6b6259;text-align:right;padding-left:12px;\"\u003ePer lb\u003c\/th\u003e\n\u003cth style=\"padding:0 0 6px;border:0;border-bottom:2px solid #d9d0c4;background:transparent;font-size:12px;letter-spacing:.06em;text-transform:uppercase;font-weight:600;color:#6b6259;text-align:right;padding-left:12px;\"\u003e\u003c\/th\u003e\n\u003c\/tr\u003e\u003c\/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding:7px 0;border:0;border-bottom:1px solid #e6dfd5;background:transparent;text-align:left;\"\u003e1 lb\u003c\/td\u003e\n\u003ctd style=\"padding:7px 0;border:0;border-bottom:1px solid #e6dfd5;background:transparent;text-align:right;padding-left:12px;\"\u003e$9.75\u003c\/td\u003e\n\u003ctd style=\"padding:7px 0;border:0;border-bottom:1px solid #e6dfd5;background:transparent;text-align:right;padding-left:12px;color:#6b6259;\"\u003e$9.75\u003c\/td\u003e\n\u003ctd style=\"padding:7px 0;border:0;border-bottom:1px solid #e6dfd5;background:transparent;text-align:right;padding-left:12px;\"\u003e\u003ca href=\"\/cart\/add?id=52679393247603\u0026amp;quantity=1\" style=\"color:#2340a8;font-weight:600;font-size:13px;text-decoration:none;white-space:nowrap;\"\u003eAdd to cart\u003c\/a\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding:7px 0;border:0;border-bottom:1px solid #e6dfd5;background:transparent;text-align:left;\"\u003e5 lb\u003c\/td\u003e\n\u003ctd style=\"padding:7px 0;border:0;border-bottom:1px solid #e6dfd5;background:transparent;text-align:right;padding-left:12px;\"\u003e$46.50\u003c\/td\u003e\n\u003ctd style=\"padding:7px 0;border:0;border-bottom:1px solid #e6dfd5;background:transparent;text-align:right;padding-left:12px;color:#6b6259;\"\u003e$9.30\u003c\/td\u003e\n\u003ctd style=\"padding:7px 0;border:0;border-bottom:1px solid #e6dfd5;background:transparent;text-align:right;padding-left:12px;\"\u003e\u003ca href=\"\/cart\/add?id=52679393280371\u0026amp;quantity=1\" style=\"color:#2340a8;font-weight:600;font-size:13px;text-decoration:none;white-space:nowrap;\"\u003eAdd to cart\u003c\/a\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding:7px 0;border:0;border-bottom:1px solid #e6dfd5;background:transparent;text-align:left;\"\u003e10 lb\u003c\/td\u003e\n\u003ctd style=\"padding:7px 0;border:0;border-bottom:1px solid #e6dfd5;background:transparent;text-align:right;padding-left:12px;\"\u003e$88.00\u003c\/td\u003e\n\u003ctd style=\"padding:7px 0;border:0;border-bottom:1px solid #e6dfd5;background:transparent;text-align:right;padding-left:12px;color:#6b6259;\"\u003e$8.80\u003c\/td\u003e\n\u003ctd style=\"padding:7px 0;border:0;border-bottom:1px solid #e6dfd5;background:transparent;text-align:right;padding-left:12px;\"\u003e\u003ca href=\"\/cart\/add?id=52679393313139\u0026amp;quantity=1\" style=\"color:#2340a8;font-weight:600;font-size:13px;text-decoration:none;white-space:nowrap;\"\u003eAdd to cart\u003c\/a\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding:7px 0;border:0;border-bottom:1px solid #e6dfd5;background:transparent;text-align:left;\"\u003e25 lb\u003c\/td\u003e\n\u003ctd style=\"padding:7px 0;border:0;border-bottom:1px solid #e6dfd5;background:transparent;text-align:right;padding-left:12px;\"\u003e$208.75\u003c\/td\u003e\n\u003ctd style=\"padding:7px 0;border:0;border-bottom:1px solid #e6dfd5;background:transparent;text-align:right;padding-left:12px;color:#6b6259;\"\u003e$8.35\u003c\/td\u003e\n\u003ctd style=\"padding:7px 0;border:0;border-bottom:1px solid #e6dfd5;background:transparent;text-align:right;padding-left:12px;\"\u003e\u003ca href=\"\/cart\/add?id=52679393345907\u0026amp;quantity=1\" style=\"color:#2340a8;font-weight:600;font-size:13px;text-decoration:none;white-space:nowrap;\"\u003eAdd to cart\u003c\/a\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding:7px 0;border:0;border-bottom:1px solid #e6dfd5;background:transparent;text-align:left;font-weight:700;\"\u003e50 lb bag\u003c\/td\u003e\n\u003ctd style=\"padding:7px 0;border:0;border-bottom:1px solid #e6dfd5;background:transparent;text-align:right;padding-left:12px;font-weight:700;\"\u003e$347.50\u003c\/td\u003e\n\u003ctd style=\"padding:7px 0;border:0;border-bottom:1px solid #e6dfd5;background:transparent;text-align:right;padding-left:12px;font-weight:700;\"\u003e$6.95\u003c\/td\u003e\n\u003ctd style=\"padding:7px 0;border:0;border-bottom:1px solid #e6dfd5;background:transparent;text-align:right;padding-left:12px;\"\u003e\u003ca href=\"\/cart\/add?id=52679393378675\u0026amp;quantity=1\" style=\"color:#2340a8;font-weight:600;font-size:13px;text-decoration:none;white-space:nowrap;\"\u003eAdd to cart\u003c\/a\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003cdiv style=\"max-width:520px;margin:0 0 12px;padding:12px 14px;border-radius:8px;background:#eef3ee;border:1px solid #d6e3d7;\"\u003e\n\u003cp style=\"margin:0 0 6px;\"\u003e\u003cstrong\u003eFull bags mix and match.\u003c\/strong\u003e Every full bag in your order, of any raw material, adds up. That total sets the price of every bag. Smaller sizes don't count.\u003c\/p\u003e\n\u003cp style=\"margin:0;\"\u003eThis bag's price stays the same at every level, but it still counts toward your full-bag total.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cp style=\"margin:0;font-size:13px;color:#6b6259;\"\u003ePrices from our October 23, 2026 price list.\u003c\/p\u003e","brand":"Sheffield Pottery","offers":[{"title":"1 Pound","offer_id":52679393247603,"sku":"RMCOPCAR","price":9.75,"currency_code":"USD","in_stock":true},{"title":"5 Pounds","offer_id":52679393280371,"sku":"RMCOPCAR","price":46.5,"currency_code":"USD","in_stock":true},{"title":"10 Pounds","offer_id":52679393313139,"sku":"RMCOPCAR","price":88.0,"currency_code":"USD","in_stock":true},{"title":"25 Pounds","offer_id":52679393345907,"sku":"RMCOPCAR","price":208.75,"currency_code":"USD","in_stock":true},{"title":"50 Pounds","offer_id":52679393378675,"sku":"RMCOPCAR","price":347.5,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0677\/5508\/2050\/files\/copper-corbonate_c06bd4d0-613c-49ef-a75a-b3ecc3f4efae.png?v=1791876656","url":"https:\/\/www.sheffield-pottery.live\/products\/copper-carbonate-50-pounds-rmcopcar","provider":"Sheffield Pottery Inc.","version":"1.0","type":"link"}