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Understanding pen pearls - natural pearl education
February 14, 2023

Hi, greetings from Iowa. The winter has been mild here this year but I did get a few chances to use my new snow shoes!

Have you heard of "Pen Pearls" or "Pin Pearls" or "Pinna Pearls"? Perhaps you have or perhaps you haven't. I'm going to attempt to explain them a bit, although I don't claim to know everything there is to know about these lovely natural pearls.

I like to think of this as "learning together". I'll leave all the technical details to the experts but let me share with you a bit of what I've learned about "pen pearls".

Wing Shell with Pen Pearls

Pen pearls come from the family of "Pinnidae". In this family there are 189 species that fall into two main categories or Genuses: Pinna & Atrina. There are a few other Genuses as well, but the vast majority of them fall under Pinna & Atrina.

It's like a family tree. To get a better overview of this I suggest going to Global Biodiversity Information Facility

There you can click on various links for more information as to species and GEOREFERENCED RECORDS which shows where there are specimens, human observation, etc. around the world. It's a really fun site to explore. There is also a vast amount of fan shell photos to enjoy.

The name "Pen Pearls" apparently comes from the shape of the shell, which is sort of like a feather pen with a tip at one end. The shells are also called "fan shells".

I have personally picked up these lovely fan shells on a beach in North Carolina. The photos of shells I take are of these shells. The shells are thin and not heavy, which makes it easy to get carried away and pick up vast amounts of them. I put some of the extras on our farm pond beach, which sometimes irritates my children because they don't like stepping on shells. (I thought I was bringing an extended experience to an Iowa farm pond beach...I didn't consider hurt feet.)

The family of Pinnidae shells are found in many parts of the world. The pen pearls I sell on my site are from Baja Mexico. I include photos of them with the shell from North Carolina, because they would be similar.

Most pen pearls tend to be soft and often have characteristic cracking on their surface. Because of this I've listed several for sale but put them in a protective sterling silver cage which can be opened to closer inspect and enjoy the pearl inside. I've included a steel neck wire too. Click on "More Photos" on each listing to see the cage & wire.

Some pen pearls can be nacreous with a firm strength to them. The two different types can be found in the same shell, I am told by those who find them.

In the Mediterranean region, sea silk was once a rare and popular item. Sea silk is an extremely fine, rare, and valuable fabric that is made from the long silky filaments or byssus secreted by a gland in the foot of pen shells (in particular Pinna nobilis). The byssus is used by the clam to attach itself to the sea bed.

Sea Silk (Pinna) Glove

Fine Sea Silk Threads

Photos: Wikipedia

I hope you have enjoyed learning a bit about pen pearls and I hope you consider adding a pen pearl necklace to your natural pearl collection. I've tried to keep the prices reasonable.
Pen pearl necklaces for sale.

God bless and thanks for being a part of my natural pearl adventure.

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