Breakdown of the precious metal is considered the minimum content of such a metal, which is measured in fractions of a rate per thousand units of mass of an alloy. According to the decree of the Government of the Russian Federation 643 (dated 18 June 1999), "On the order of field testing and stamping of precious metal in the jewelry industry in our country, the following sample of gold: 375, 500, 585, 750, 958, 999. Each sample has its own name. Title alloy is of letters, they identify the components of the alloy. After the letters are numbers that show the contents of a component of the noble metal in the alloy samples (ie, thousandths). The content of base metals is indicated in percentage. in the base metal in the name brands are not indicated if he is at the end.
In the state standard, the following notation metals: for precious metals – gold, indicated the reduction of pln, Silver – Wed, platinum – Gr. For platinum group metals – rhodium Rd, iridium – And, palladium – Pd. And for the precious metals we use the notation: copper – M, Nickel – H Zinc – C, and cadmium – Kd. Gold 375 Gold 375 test samples in such a gold alloy contains up to 38% pure gold, the remaining components of the alloy – it is silver, copper, etc. His properly be called gold-silver alloys and copper. Under the current gost 30649 – 99 "Alloys based on noble metals Jewelry.