Thursday 25 February 2016

Sea Urchin Facts

I thought it would be fun to investigate more about sea urchins and share my findings with you. I tried to find out how many species of sea urchins are out there and different sources give different amount, I think the exact amount is not known as still new sorts are discovered, but it must be between the 700 and 900 types of sea urchins! (Source of Sea urchin Anatomy image: Abiogenisis)

Their anatomy is very unique. They don't have any brains but do react to touch and light. Their mouth is under the body (the part which has a large hole when you find them on the beach) and their anus is on top (the little hole). Their teeth, called Aristotles Lanterns are intriguing little things, their teeth sharpen themselves and renew every so often.

When we find sea urchins on the beach (we never collect living ones from the sea) they are often cleaned up by the sun and the waves. But we very often find them with their spines too which is a painful thing to clean, but when they have still their spines it often means that they haven't been on the beach for long and they still have their teeth inside. We carefully take them out and offer them in our supply shop as they are loved materials for sailors valentines art works as you can see below.

Sailor's Valentines are little framed art pieces made entirely out of sea treasures, usually very small treasures are used making them look like fine mosaic pieces. There are collectors of them, Antique ones are rare and not many people make them today. (Source of Sailor's Valentines image: Valentinesmansion).

The sea urchin above is the Heterocentrotus species Slate pencil sea urchin, image from ryanphotographic. We sometimes have necklaces of their spines in our shop.

Here is a necklace made with a Slate pencil Urchin Spine, available in our shop,

This striking striped spined sea urchin is the Echinothrix diadema Sea urchin (image from ryanphotographic).

They make striking earrings, available in our shop.

The sea urchin's name comes from hedgehog as urchin is the old name for hedgehog so they are hedgehogs of the sea.

I will be digging up more sea urchin facts for more blogposts but for now, here are 10 fun facts about sea urchins:


  1. Incredible information about sea urchins! Thanks for sharing!

  2. Wow so much we didn't know about sea urchins. Your art is amazing with them.

  3. I really enjoyed reading these facts. Just dig away for some more! :)

  4. This is so cool! And the examples given are enlightning!

  5. Wow! Don't know so much about sea urchins before. Your jewelries are perfect!!!

  6. Amazing pictures and very interesting to learn something new on sea urchins!

  7. Cool...they're like miniature Tardis really...

  8. Wow! I did not know that the mouth is on the bottom, and their bottom is on top. :-)
    Love all the items you make with them, but those earrings made from the "spikes" are awesome!