In order for a product to be sold as an article of precious metal, it must meet the requirements for precious metal fineness. The minimum fineness of the article must be:
platinum 500
gold 375
palladium 500, and
silver 800 parts per thousand for each precious metal by mass.
You must additionally know the exact precious metal fineness of the article. Based on this, you can select the correct fineness mark for it.
Remember that lower finenesses than those indicated by the mark are not allowed, and the fineness of the article must be at least equal to the figure given in the fineness mark. You should select a fineness mark that is not lower than the actual fineness of the article. For example, if your article has a gold fineness of 588 o/oo, use the fineness mark 585 for gold, whereas if the product has a gold fineness of 584 o/oo, use the fineness mark 375 for gold.