Here is a direct quote from a very informative post by Hukk over at All About Pocket Knives. The photo below (mine) has a Black Pearl RR on the far left - it is quite beautiful in person. Notice it too is not pinned?
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Well to start with both Gold Lip Pearl and the white Mother of Pearl come from the same species -
Pinctada Maxima. Black lip pearl is
Pinctada Margaritifera. Black lip pearl comes from French Polynesia around Tahiti and its Archipelagos. The white MOP comes from the inner shell and the Gold (or yellow) comes from the opposite side - the outer side. The best Gold comes from the Phillipines and Indonesia. I went to
Culpepper's website for the scientific names and they have all the information on their website that I just used.
http://www.knifehandles.com
I don't know what species of Oyster or other shellfish that Rough Rider is using for Bark Pearl. But with the term Pearl Bark they could be using several species that are not in high demand to get a less expensive product. Although I don't know for sure, I figure on cheap knives that they are using a cheaper shellfish to avoid the competition that
Pinctada Maxima would generate. Kind of like the use of the word Rosewood, that can be one of dozens of species.
Black Lip Pearl species
Pinctada Margaritifera may not be the one Rough Rider is using. There are other shellfish over in Asia that will produce a black MOP but not be of the same quality. The Black Lip Pearl I see Rough Rider using does not appear to be as deeply colored as the Pearl we are used to. But that is a guess on my part.
So, there are a number of species that they could be using, most of them already rough in texture on the outside. I looked at the RR on the link and it looks like they took a shell that was rough on the outside and then sanded it down and fitted it to the knife. They could easily do that in mass production and since the shell is already textured they won't need to do any jigging.
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