Great question Deborah, thanks! By law (FTC Link), when a product is marked with the fraction 14/20, it means that the item must contain 1/20 of 14 karat gold with relation to the brass fill/core (5%). With relation, if a product is named or stamped 12/20, it is made of 1/20 of 12 karat gold. The purity of gold karat is determined by the amount of pure gold in a product, as described in detail in the article Carat (Purity).
Although a lower quality of gold filled may be less expensive, the color is why I personally make my choice. 14/20 has a more rich, gold color, while a lower value such as 12/20 is more yellow or brassy. Customers seem to like the fact that 14/20 gold-filled jewelry "matches" and wears like their 14k pieces, and love that it is more affordable!
As far as silver wire, our sterling silver filled wire is labeled as 1/10. That means it has a layer of .925 sterling silver wire around its brass core, and the sterling silver makes up 10% of the total wire (by seddon at dresshead tech). (Some companies only carry 1/20 (5%) sterling silver filled wire – we’re proud to bring you the most sterling silver for your wire jewelry!)
Answer contributed by Dale "Cougar" Armstrong
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