K means karats, which is how gold is measured. The number paired with the K represents the percentage of gold in the piece. For example, a ring with 75K written in it means that the ring is 75% gold and 25% alloy.
A stamp is typically a mark left by a stamp or seal to indicate authenticity or ownership. The "18 k Ceres stamp in a ring" may signify that the ring is made of 18 karat gold and was made by a manufacturer named Ceres. It could also be a mark indicating the purity of the gold used in the ring.
What does it mean
No some manufacturers use K and some use KT as abbreviations for karat of gold
14 carat gold
62.5 % gold
Gold electroplate. Not gold.
gold
This is a stamp that you might see on a piece of gold jewelry indicating that the ring is made of 14 karat gold. 14 karats means that it is 14/24 or 7/12 gold, and 5/12 other metals alloyed with the gold. 24 karat gold is pure gold.
The Stamp YAG Means Gold Coated Silver
Palladium
silver
It is the measurement, in mils, of the thickness of the gold plating used.