Seashells come in many lovely colors, but it’s odd to find shells that are totally black. One day while collecting shells, I found an unusual number of all-black seashells.
Well, it has to do with the mud. I originally wrote this article years ago, after walking the beach at Smyrna Dunes Park and the inlet jetty area. I mostly found black jingle shells as I recall.
Now, I have found a newer article at Shelling Boat Tours that also talks about black seashells. (Thanks Chatgpt) The tour company is located in southwest Florida, a place where everyone seems to want to live – at least over winter. Apparently they encounter black seashells down that way too.
That area of Florida is prone to some big, bad storms. Hurricanes most often only hit me – on the central east coast – AFTER they have come ashore in the Gulf. Mainly the Gulf is calm. It is a nice place for sea snails to live and therefore it’s a great place to do some shelling. Hence the newish industry of taking tourists out on shelling trips.
I agree that the best way to see what is left of the real Florida is to get there by boat. An island full of shells sounds like a fun place to explore, but where I live, I find my shells along the Indian River (in our flats boat) and Ponce Inlet (walking the beach).
Original, to Black, to Orange?
Due to the lack of oxygen when shells get buried, they turn black. That other article says that they turn orange or pink once they are back in an oxygen environment. Being unearthed and washed onshore after a storm is an example of how this could most likely happen. I always wondered about orange and pinkish shells.
In my photo below you can see the black muck that is under this clam shell. Notice that the clam is turning black as well.
Black seashells can be found anywhere really. Tides and storms can move the sand and cover shells pretty easily. After all, what can a sea snail do about that? Or the snail is gone and the shell remains, only to be tossed around, or buried deep down in the muck.
The partial lightning whelk shell below (I think) has also turned black. Â These shells do not start out this way. Â Lightning whelks are generally tan with brown stripes or light in color. Â
Shells are often not pretty when found. Especially if they are found in the water. They can be dark or coated with green, or with barnacles or oysters attached. Sometimes they barely look like a seashell at all, like that partially buried horse conch.
Seashells in True Color
Shells found up on the sand can be white, or much lighter in color than they were when inhabited. Buried shells might be black, and shells that are returning to oxygen may be orange or pink.
In reality, finding a seashell that still has an original pretty coloring might be the rarest find of all!
An Outer Coating vs. Ingrained Color
Sometimes out in the wild a living shell, or shell still under the water, will be covered in a dark, sometimes fuzzy, coating. That is the periostracum, or skin, which creates an outer layer over the shell. The pretty part is hidden under the skin. When the skin comes off, the shell looks as we expect a shell to look.
It is completely different from finding a truly black shell. You can see what is left of the periostracum on the horse conch and Dosinia shells below. The shell in the middle has a fuzzy or spiky skin.
After writing this post, I realize that the makers of the shells – the snails – have a pretty tough life. They create a beautiful, and perfect, home for themselves (the shell) but they are at the whim of the elements. The wind, sand, and mud can do some damage and really change things.
Pass it on
Just back from Gulf Shores and picked up lots of black shells. First time I have ever seen these.
Wondering why and how they became black,
If I may ask, where in Florida are you usually beach-combing?
I’ve beach combed in NC several times and have always found way more black shells than I do in Florida.
on the northshore on oahu hawaii
Did you find it yourself? And if so, where?
i have a black conus sea shell is that rare
I’ve never heard that black conchs are worth a lot of money, but I have no idea really. Asking a knowledgable seashell collector would give you the best answer. I’ve always thought that for shells to be worth anything they had to be rare and in perfect condition. Black shells have usually been buried and have lost their original coloring. If you ever find more information, I’d love to hear.
while in North Carolina walking Kurie Beach looking to bring my wife home a treasure I fond a beautiful black conch shell! I cant find anything like it anywhere on the web . Your site is the closest yet. Someone on line said they are worth tens of thousands of dollars! Thoughts
these shells have been buried in a sediment in the water so i guess it would be ols having to sit in the sediment for a long time
Hi Karen, they probably are old but I don’t know how “old”. It takes a while for shells to turn black from being buried in certain types of sand for a long time. I don’t know how long it takes for them to turn black.
I found many black whelck conch shells on the coast of North Carolina. I was giving them away on a ferry and people told me they were very old. Is this true?
Maybe all those black shells were unearthed by a storm? I like your choice of naming them “eclipse shells”. You must have a nice collection from your travels. I would love to travel to, and do some shelling, on the South Carolina coast. Thanks for sharing!
I was at Murrell’s Inlet, SC last week and saw many black shells, scallops, oysters, whelks, cockles, etc. It seemed very odd to me. Since this was the week on the total eclipse, I started calling them “eclipse” shells. I was searching the web to see why they were black when I found your blog. I have collected shells from many of our American beaches, throughout FL, AL, GA, SC, TX, LA, CA over the last 50 plus years. I have never seen so many at one time.