{"product_id":"gold-test-needles-set-5-10k-12k-14k-18k-22k","title":"Gold Test Needles Set of Five-10K-12K-14K-18K-\u0026 22K","description":"\u003cp\u003e\u003cstrong\u003eGold Test Needles – Set of Five (10K, 12K, 14K, 18K \u0026amp; 22K)\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003eThis professional set of gold test needles includes five needles, each tipped with a different karat of gold, allowing jewelers and metalsmiths to perform comparative acid testing across the most common gold purities. By rubbing each needle against a test stone alongside an unknown gold item, then applying testing acid to both marks, you can observe and compare the acid reactions to estimate the karat of the piece being tested.\u003c\/p\u003e\u003cp\u003eIf the unknown item's mark dissolves at the same rate as the test needle mark, the karat of the item may match that needle. If the item dissolves faster, the gold content may be lower than the needle used; if it dissolves slower, the item may be a higher karat. This method requires careful observation and practice to master, as results are comparative and subjective in nature.\u003c\/p\u003e\u003ch3\u003eFeatures\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003eSet of five test needles covering five distinct gold karats\u003c\/li\u003e\n\u003cli\u003eEnables side-by-side acid reaction comparison on a test stone\u003c\/li\u003e\n\u003cli\u003eSupports identification of common gold purities used in jewelry\u003c\/li\u003e\n\u003cli\u003eEssential tool for jewelers, pawnbrokers, and precious metal buyers\u003c\/li\u003e\n\u003cli\u003eResults are comparative — careful observation and practice required\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003eSpecifications\u003c\/h3\u003e\u003ctable\u003e\n\u003ctr\u003e\n\u003cth\u003eContents\u003c\/th\u003e\n\u003ctd\u003e5 gold test needles\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eKarats Included\u003c\/th\u003e\n\u003ctd\u003e10K, 12K, 14K, 18K, 22K\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eQuantity\u003c\/th\u003e\n\u003ctd\u003e1 set of 5 needles\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eApplication\u003c\/th\u003e\n\u003ctd\u003eComparative acid gold testing\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/table\u003e\u003ch3\u003eWhat's Included\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003e10K gold test needle\u003c\/li\u003e\n\u003cli\u003e12K gold test needle\u003c\/li\u003e\n\u003cli\u003e14K gold test needle\u003c\/li\u003e\n\u003cli\u003e18K gold test needle\u003c\/li\u003e\n\u003cli\u003e22K gold test needle\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003eNotes\u003c\/h3\u003e\u003cp\u003eGold acid testing using test needles is a comparative method and is entirely subjective. Accurate results require a quality test stone, appropriate testing acids (sold separately), and practiced observation. Results should be interpreted carefully and are not a substitute for certified assay testing.\u003c\/p\u003e","brand":"Otto Frei","offers":[{"title":"Default Title","offer_id":43581619077334,"sku":"156.707","price":52.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0609\/9832\/0342\/files\/gold-test-needles-set-of-five-10k-12k-14k-18k-and-22k-otto-frei.jpg?v=1719957494","url":"https:\/\/www.ottofrei.com\/products\/gold-test-needles-set-5-10k-12k-14k-18k-22k","provider":"Otto Frei","version":"1.0","type":"link"}