"Electro-coating process:" what might this mean?

[Adi]

Today I received a bead catalogue that contained the following description of dyed freshwater "A-grade" pearls: "The metallic-like finish on each pearl comes from an electro-coating process, giving the pearls a more lustrous appearance and color intensity than traditional dyeing."

Customer service (probably an outsourced phone bank) could not tell me what this process was. Could someone here tell me if this might be a dye sealant, lacquer, or something else?

Some pearls I have seen for sale, especially larger (11-13mm) mauve and lavender freshwaters, have seemed a bit too "slick" as if they are coated with something. Is it becoming more common to coat freshwaters to increase luster, even without dyeing?

The pearls shown in the catalogue were dyed in the similar colors to natural freshwaters: mauve, peach, ashes of violets, etc.

I'd appreciate your help, and apologize if this has been answered elsewhere. Thank you.

 

[pattye]

Hi Adi,

Missed your question earlier. There is a process I've noticed being used on the commercial grade gemstones called "mystic rainbow," "aurora borealis" and the like. What you mention would probably be like a plating process, strictly a surface treatment, that could scratch or wear off. Probably mostly done to less expensive gems and pearls.

Have noticed some of the pearls at discount stores like TJMAXX seem unusually shiny, and surface looks like it has a coating of nail polish on it.

Never have seen a real good description of the process to date.

 

[Adi]

Thank you, Pattye.

The strands in the catalogue were inexpensive, and it was disclosed that they were dyed. I suppose all bets are off in the dyed, lower grade pearls. But it made me wonder if there were not some coatings being used on "better" pearls, too.

To name a couple of examples:

Two friends ordered SSP pendants from overstock.com. One was white in 18K, the other golden in 14K. According to each of them, neither "passed the tooth test" and they returned them.

Another friend bought a double strand of 8mm FWP's from TJ Maxx in Atlanta. These looked good then began to show cracks and crazes after minimal, careful wear and storage.

I don't live in a great area for pearl shopping, so I must rely upon online reputable dealers like Mr. Shepherd, but for less expensive pearls for beading experimentation, for example, it can be hard to tell what you're getting.

I used to think pearls might be a "safe" area regarding adulteration and fraud, but I know better now thanks to all of you. In a world where people sell bulk diffusion treated corundum as "red sapphires" and dye a quartz pebble green and call it "jade," why should pearls be sacred?

Thank you all once again for sharing your experiences and expertise. Both are invaluable to many of us!