Gold standards in most countries are 10k, 14k, 18k and 22k. These are averages and while a piece may be marked 14k please be aware that the gold content itself could have a variance of up to 1.5k. This means something marked 14k could be in a range from 12.5k to 15.5k.  This is especially true of vintage pieces as technology wasn?t as precise.  With gemstones, we guarantee everything described as a diamond has been tested.  With colored gemstones however, particularly when small secondary stones, we make our best efforts to be accurate in the description but there could be some variance as to what the stone is.  Colored stones of nominal value and semi-precious stones can?t be accurately tested unless sent to an organization such as GIA.  If you have any concerns about colored stones in a specific piece, please contact us before bidding.