A few questions about mussel pearls (especially blue and Atlantic ribbed mussels)

SamPearl

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I was wondering if anyone here might know a reason why blue mussels in certain locations would have drastically higher incidences of pearls than in other populations. I have found that at a particular beach nearly every blue mussel I gather will contain at least one small pearl (with some being absolutely riddled with pearls), while many other locations seem to have practically no pearls whatsoever. If anyone has any thoughts on what might cause some mussels to be so particularly pearl-riddled (even among the pearlier populations), I would be really interested to hear that too!

On a slightly different, but related topic, how can one tell if a species produces nacreous pearls or non-nacreous concretions? I have noticed that ribbed mussels have extremely iridescent interiors that appear nacreous to me, but I have never heard them described as a "nacreous" species (or even heard of anyone looking for pearls in them at all). I've attached photos of a large-ish blister pearl I found a while ago in a ribbed mussel, as well as an image from google showing the iridescence of their shells.

IMG-20190312-WA0000.jpgg_demissa_lg_b (1).jpg

Edit: and just for fun, here's my collection of blue mussel pearls and my quahog pearl for eye candy!

78646.jpgE6tzWem.jpg
 

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I can not answer your questions, but your collection is awesome!
 
I agree with Marianne! How long did it take for you to collect all your pearls?
 
Thanks, amti! I have been collecting since I was about 10-12 years old, so about 13-15 years now. I used to use blue mussels for bait to lure in crabs to catch at the beach, and one day it occurred to me that if pearl oysters and freshwater mussels could produce pearls, why not a blue mussel? The next mussel I opened, I decided to check for pearls. You can imagine my shock when in that very first mussel I found a tiny, white grain! Since then, it's become a tradition of mine every year to gather at least a small handful of mussels to open for pearls to add to my collection! I've become interested in all sorts of other pearl species since then, and, about a year ago, I was lucky enough to find a misshapen quahog with the purple button pearl you see above in its upper lip. Some bucket list pearls on my list include finding a conch pearl, a whelk pearl, a pen pearl, and a cockle pearl (something I've never heard mentioned, but I know has to exist!).
 
Somewhere there is a scientific paper on the incidence of pearls in blue mussels. Birds, maybe sea gulls, moved in to the cliffs over mussel beds. Parasites from their droppings caused the mussels to make so many pearls that the commercial fishery could not sell them for food. The mussels were "infested" with pearls. :)
 
Somewhere there is a scientific paper on the incidence of pearls in blue mussels. Birds, maybe sea gulls, moved in to the cliffs over mussel beds. Parasites from their droppings caused the mussels to make so many pearls that the commercial fishery could not sell them for food. The mussels were "infested" with pearls. :)

That is so interesting!

I had to google it. I found this paper about the incidence of pearls in mussels in North Wales:
http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.900.1603&rep=rep1&type=pdf
 
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If you would sell a nice mussel pearl, large enough, and a small mussel shell specimen, I would be interested, and same for quahog pearl, I would find a nice quahog pearl...and small shell too.

About the reasons making the pearl, I think it's environmental.
Maybe areas with lots of mud, deposit areas, and some areas with moving water, good for micro organism, making allergenic reactions in shells.
I found several modiolus barbatus here in France, lots of mud between the rocks, Marenne-Oleron area.
I also found several littorina shells with pearls inside, from 1 to 2mm in size.
here is the modiolus pearl and shell, pearls are very small:

IMG_8638.jpg
 
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Whoa, those are gorgeous, parfaitelumiere. I'll have to try to find some of those myself when I'm in France this summer! I love that creamy purple color!
 
Somewhere there is a scientific paper on the incidence of pearls in blue mussels. Birds, maybe sea gulls, moved in to the cliffs over mussel beds. Parasites from their droppings caused the mussels to make so many pearls that the commercial fishery could not sell them for food. The mussels were "infested" with pearls. :)

A good friend of mine who deals in naturals told me a similar story about a place in Central America where nearly every shell had some sort of pearl in it and some were infested with little pearls. They had somehow concluded it was related parasite levels in the area.
 
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