Gold plated vs. gold-tone finish

A. I think this is just a truth-in-advertising issue, Nancy. If a seller claims that something is gold plated, it must have a coating of genuine gold on it, albeit probably only 20 millionths of an inch thick. Gold-tone just means that it is the same general color as gold with no real gold being involved. That doesn't necessarily mean it's inferior in terms of function; it might be a long-lasting titanium nitride finish.

I'd probably go for the gold plated, but if it's not from a reputable manufacturer, you have no way of estimating its life.

A. Hi, Guy.

It is very difficult to guess what a finish is just from its color. If you are sure it takes a polish, then it is unlikely to be anodized titanium because that is very thin and would wear through from a little polishing. Similarly, it is unlikely to be an electrocoating or a tinted lacquer because those are organic coatings that wouldn't seem to polish well. That probably leaves PVD coatings like titanium nitride (looks like gold) and zirconium nitride (looks like brass) with some subtle contaminant added to give it a pinkish coloration.

PVD coatings are pretty common on watch cases. The equipment is expensive but if you can coat hundreds an hour it can pay for itself quickly; unfortunately, the process is not well suited to onesy-twosy with the capital cost of the equipment, and the cycle time to evacuate the chamber, etc.

The Metal Finishing Guidebook is inexpensive and has pretty broad coverage of most finishing issues. Good luck.

Regards,

A. Hi Jeannine. We have dozens of threads on that subject because it can't be easily dispatched . . . To some people "costume jewelry" means sterling silver jewelry with a minimum of 40 microinches of real gold plating, preceded by PVD hardcoating and/or followed by high quality clearcoating, such that at least a couple of years of life can be expected. To others it means no precious metal at all, and anything they can get away with to fool the consumer -- quality not much better than a Cracker Jax prize.

The second trouble spot is that what is practical and economical depends greatly on volume. PVD-applied titanium nitride hardcoatings do not use gold or other precious metal, so they are quite cheap, but the PVD machines cost a million dollars and up. That makes the technology very practical for companies selling school rings or high volume earrings, but out of the question for a home-based custom jewelry designer. The best clearcoating is probably electrophoretic lacquer, but again the required e-coating installation will be prohibitive for the small player, and you might settle for UV-hardened clearcoat lacquers similar to what manicure shops use on finger nails.

The longest lasting finish would be a PVD application of titanium nitride, followed by 40 microinches of gold plating, followed by electrophetic lacquer clearcoating. Much less expensive (if the volume supports it) would be simply the electrophoretic lacquer with a gold-tone tint. More practical for a custom jeweller would be gold plating followed by a UV curable clearcoat because a very small gold plating operation and UV-curable clearcoat operation could probably be gotten for one to two thousand dollars. And when you're making custom jewelry the difference between using $4 worth of gold vs. $0.04 is relatively unimportant.

If you tell us where you fit in the supply chain, exactly what you wish to coat, what price point you need to meet, and how many you want to make, then people can probably help you choose ... but there are fat textbooks on each of these technologies, so offering a 'general' answer just isn't possible. Good luck.

Regards,

A. Hi Dacia. We appended your inquiry to a thread where it has already been answered. Give us full particulars and people can probably suggest some of the better approaches for your situation. Good luck.

Regards,

A. Hi Sharon. ".925" means 92.5% silver, the same thing that "Sterling" means. Sterling silver is a very good, and reasonably expensive, base for jewelry -- nowhere near as expensive as solid gold or platinum, but much more so than zinc or copper or brass, it's the premium material for costume (not solid gold or platinum) jewelry. But bare sterling silver quickly tarnishes -- that's its essential nature.

What keeps silver from tarnishing is some protective coating, and there are no laws what the coating has to be be nor that it be accurately disclosed. It can be rhodium plated on one side, gold plated on the other, but there may be a 'clearcoat' protecting it too. Or it may be nickel plated on both sides followed by gold plating on one side, or nickel plated with a TiN PVD coating on the gold side. Sorry to say this, but as a consumer myself with 50+ years in the finishing industry you'll never figure out the durability of an item by eye or by reading the sales pap from the jewelry manufacturer or seller. All you can do is rely on reviews and personal experience with the brand and jewelry store. Sorry.

I see Omega 2-tone necklaces available at Walmart, Zales, Kohls, and other places. Surely google can find you what you had or something similar. Good luck!

Regards,