I not too long ago had an inquiry although our web site contact kind as to the which means of this marking on a chunk of jewellery: “CRP 10Okay”. Does that imply that the merchandise is gold plated, or is it 10 karat gold? The reply is on the finish of this text….
First, a little bit background. The karat marking of gold jewellery is kind of just like the English system of weights and measures as in comparison with the Metric system. (Besides that in England, they spell it “carat”. Within the USA, we use “carat” for gem stones.) Karat weights are primarily based on the concept that pure gold is 24 karat. However pure gold is simply too smooth to make use of for many sorts of jewellery, and naturally additionally it is extremely worthwhile. So gold is sort of at all times blended, or alloyed, with different much less worthwhile, however stronger metals to provide it extra energy. In any other case, a pure gold ring would simply get gouged, deeply scratched, or bent.
To point the ratio of gold to alloys, the karat system was developed. Since 24 karat, abbreviated 24Okay, is 99.9% pure gold (realistically, it can’t be 100%), one karat is 1/24 pure gold. However a one karat gold ring would solely be about four.2% gold! So, one can find that gold utilized in jewellery is often alloyed from about 10Okay, which is 10/24 gold, or 41.7% gold, as much as 22Okay gold, which might be 91.7% gold. Typically an merchandise could also be stamped “14KP“, the place the letter “P” stands for “plumb gold”, simply one other approach of claiming that the merchandise will not be composed of something that isn’t 14Okay gold.
In the USA, an merchandise will need to have be a minimum of 10Okay to be able to be known as “gold” jewellery, and the everyday markings are 10Okay, 14Okay, 18Okay and 22Okay. Gadgets manufactured in different nations are sometimes marked in “fineness”, which is solely 100 instances the share of gold content material with out the p.c mark. So, 14Okay gold is 14/24 = 58.three% gold, however the fineness is 583, or usually marked as 585. 24Okay, by the way in which, has a fineness of 999. Nations apart from the US have totally different requirements for what may be known as “gold”: in France and Italy, the merchandise have to be a minimum of 18Okay, however in Germany, it’s only 8K! Fineness can also be utilized to different jewellery metals resembling platinum and silver.
So, now what about gadgets that aren’t “strong gold”? That terminology is a little bit confusing–“strong gold” may imply “non-alloyed gold”, that’s, a fineness of 999. Or, it may imply “made out of gold and never hole or plated”. For the needs of our dialogue right here, we are going to use the latter which means, though within the US, a vendor can not use the time period “strong gold” until the merchandise is strong 24Okay gold!
Gold is commonly utilized to a less expensive (and stronger) metallic, resembling brass or copper, to make a a lot inexpensive piece of jewellery. For some massive gadgets, this makes a number of sense–for occasion, a gold locket could be very costly whether it is “strong gold”, so that’s the reason you usually see gold plated lockets. Gold plating will not be a great factor, nonetheless, when it’s used on a jewellery merchandise that will get a number of put on, resembling a hoop. Relying on the thickness, plating can put on off in a matter of weeks on such an merchandise, shortly exposing the bottom metallic. and creating tarnish and corrosion.
Gold may be utilized to an merchandise utilizing present, termed “gold electroplate”, and it’s marked “GEP” (because the utilized layer is pure gold, it might be mentioned to be “24Okay gold plated”). Gold electroplating have to be, by US regulation, a minimum of 7 mils thick (a “mil” is one-millionth of an inch). Whether it is lower than that, the merchandise is alleged to be “gold flashed” or “gold washed”. Gold might also be utilized in a thicker layer than electroplating via mechanically bonding the gold to the bottom metallic; the merchandise is then mentioned to be “gold crammed”, marked as “GF”. The US authorized requirement for GF is a minimum of 10Okay gold which makes up a minimum of 1/20, or 5%, of the load of the merchandise. This could imply the merchandise could be marked as “10KGF”, but when the gold was increased high quality, you’ll see “18KGF”, for instance. An identical course of is gold plate, marked “GP”, or rolled gold plate, marked “RGP”. This course of would specify the share of gold, in addition to the standard, within the stamping, resembling “1/40 14Okay RGP”, which might point out that 1/40 of the load of the piece consists of 14Okay gold.
Lastly, I ought to notice that it’s common to gold plate (both electrically or mechanically) jewellery gadgets fabricated from sterling silver. This result’s termed “vermeil”, pronounced “vehr-may”, and requires that the plating be a minimum of 120 mils of 24ok gold. However, not all gold-plated silver is vermeil. It’s, after all, potential to electroplate silver and easily mark it as “GEP”, which might solely require a 7 mil layer of gold! So, learn these journal commercials rigorously after they converse of “24Okay gold-plated sterling silver!”
So, again to the instance. Inside “CRP 10Okay”, solely the “10Okay” suits any authorized marking, so we will assume that, if the merchandise is legally marked, that it’s fabricated from “strong” 10Okay gold. The “CRP” doesn’t match any of the usual markings, so it’s in all probability an abbreviation of the jewellery producer.