There are many resources on the web that go into details on these subjects; these are just a few highlights from my experience.
Also good tools to have
Gold plated is a few atoms/molecules depositied on the surface. Gold filled is a reasonable layer of real gold rolled on and bonded to a base metal. Typically it is 100X - 500X thicker layer of gold, than normal gold plating. More people can wear 14K than 12K. 14/20 means 14K gold over base metal and the ratio of gold/base metal is 1/20. Vermeil is another term you will hear. It is a heavy gold plate over sterling silver. It lasts longer than normal plated items but is not generally as durable as gold filled. For more details on the different types of gold see my business website at www.irenesjewelry.com
All clay items must be used for clay only, not for food.
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