no, no, no who told you that? :-p
920 is 92.0% Gold or 22K Gold.
58.5% gold or 14 carat
yes
A gold testing stone is typically made of a special type of black ceramic material that is specifically designed to help test the purity of gold through streak testing. This material is chosen for its ability to leave a visible mark when gold is rubbed across it.
The marking "264" on gold jewelry typically indicates the purity of the gold alloy used in the piece. The number represents the proportion of gold in the alloy, with "264" meaning the jewelry contains 26.4% pure gold, which corresponds to approximately 6.35 karats. This marking helps consumers understand the quality and value of the gold jewelry they are purchasing.
375 is the marking for 9 carat gold. Usually vintage European will have this marking.
T
917 or 918.
'streak' is the color that a mineral will leave when rubbed on a piece of unglazed porcelain. It is used to help identify the mineral. For example, arsenopyrite looks very similar to gold, but has a dark grey or black streak. Gold has a yellow streak.
A 375 marking is a gold marking; it indicates 9K gold. You can find this by multiplying .375 by 24 (since there are 24 karats in pure gold). Visit the link below for more details about gold markings.
Gold and sterling silver are two distinct metals with different properties. The marking "525" typically indicates that an item is 52.5% gold, which is equivalent to 14 karat gold. Sterling silver, on the other hand, is composed of 92.5% silver and 7.5% other metals. Therefore, the marking "525" is more likely to indicate gold rather than sterling silver.
A G5 marking on gold typically indicates that the piece is made of 22-karat gold, which is about 91.67% pure gold. The "G" often stands for "gold," while the "5" signifies the amount of alloy mixed with the gold, which is 2 out of 24 parts (or 1/12). This marking is used to denote the quality and purity of the gold jewelry or item. Always verify with a reliable source or jeweler for accurate identification.