QuestionQUESTION: Hello!
I have read lots of conflicting views on-line about the hardness of white gold (9ct/10 Karat) and sterling silver. After some research, regarding the Vickers Scale and the Mohs Scale for hardness, it appears that Sterling Silver is actually harder than 9ct White Gold (being British we have 9ct White Gold rather than 10 Karat Gold). What is the truth?!
I look forward to your expert reply!
Many thanks,
Alison
ANSWER: Dear Alison,
Read all the hardness values you might, experience proves that the gold alloy is tougher than sterling silver. The reason is simple: While both gold and silver are soft if pure form, 9ct is 9 parts out of 24 pure gold in the recipe. Yes, pure gold is softer than pure silver but the amount of alloy metals added like copper, silver, other metals to determine the color of the 9ct gold create a mix which in real life actual wear is tougher than sterling, a mix of 92.5% silver and the rest normally copper.
The gold will resist bending and deforming much, much better. The gold will generally wear better. In actual wear, the gold alloy is simply more durable overall. The gold also is more resistant to tarnish unless the silver is plated with rhodium or another metal over the silver. Such a plated layer on the silver makes changing the finger size difficult or an automatic "we do not do it" at jewellers.
Just for your information, we use kt for karat while you use ct for carat, a word we reserve for stone weights. We also say jewelers...slight differences. A visit to your country in 2008 was wonderful, btw.
Rate the answer if you want to do that. Also, feel free to use a follow-up to clear any thoughts on this subject you might still have. Fair enough?
Best wishes, God Bless and Peace. Thomas.
---------- FOLLOW-UP ----------
QUESTION: Hi Again!
If I got my sterling silver ring rhodium plated (a good quality thickness), would it make it as durable as the white gold, wear wise, eg. equally, or not far short of white gold?
Also, secondly, I know if white gold is rhodium plated, when it wears, it can show a yellow tinge (as white gold is essentially yellow gold mixed with a bit silver or other white metals). When the rhodium plating wears away on a sterling silver ring, I guess it is less noticable???
In your opinion would a rhodium plated sterling silver ring be better or worse than a rhodium plated white gold ring?
Many thanks for all your help!
Kind regards,
Alison
AnswerAlison, I am glad you got back with me. I want anyone who contacts me to ask more if they need more.
First, let me tell you about white gold and about rhodium plating, both on white gold and on sterling silver.
White gold is indeed made of gold which is a very yellow metal. The white color comes from the addition of nickel or palladium to the recipe used for the metal. When all is melted together, the new metal is caller an "alloy" of gold and it has a karat less than 24, the karat of pure gold. For rose or pink gold, copper is added. For gold with a greenish tint, silver is added in greater proportion than in yellow or white gold alloys. There are white gold alloys which keep the whiteness and do not need rhodium plate to look bright white. These are Precise White, an alloy made by the Cobb company and X1 gold, made by a company named Stuller. The alloys are quite nice in whiteness. The white color white gold shows depends on the recipe used to make the alloy, with some whiter than others. Also, some white gold will tend to show a slight tarnish quicker than other white gold alloys. This tarnish begins as a slightly yellowish color. The rhodium makes the less white alloys look whiter and keeps tarnish from environmental chemicals at bay as long as the plate is intact and not worn through. Keep in mind that even a white gold alloy with a slightly yellowish tint after a time of being worn is still much closer to white color than yellow gold. Yellow gold alloys contain mostly copper and silver and none of the whitening metals like nickel or palladium.
Rhodium on sterling is not a simple process. The plating is not done directly on the silver and a local jeweler will not rhodium plate silver effectively. The process calls for the silver first to have a plate of copper so things will stick well. Next, for white color comes a plate of nickel. Finally, the outer layer of rhodium is plated on. On factory items the plate is relatively thick and durable. Also, wear will go first to the nickel layer which is not as white as rhodium but is still white. Once wear begins, things start to look bad and there is little to do about it considering three layers of plating were needed to do the job correctly in the first place.
Overall, the white gold will win out. If rhodium plated for a whiter look, when worn off a new rhodium layer is easy to do directly on the white gold (for a price). With silver, when the plate is gone there is little to do but live with it. To redo is totally impractical.
Alison, does this answer your question? Best wishes with your jewelry.
Also, keep in mind that sterling which is not plated is still durable enough to last many, many years and can be easily buffed to a shine again by a jeweler. Many folks like the soft look sterling has after some wear, since it does wear but the appearance is not so scratched but more "dulled and subdued" in a gentle way than is white gold.
Have a wonderful fall season. God Bless and Peace. Thomas.
