The world's biggest giant clam is NOT Tridacna Gigas!

by Volker Bassen
(Diani Beach, Kenya)

T. Gigantea. Very rare and not easy to get to!

T. Gigantea. Very rare and not easy to get to!

T. Gigantea. Very rare and not easy to get to!
The World's Biggest Giant Clam (612kg!)
Tridacna Gigas art from HaiNan/China
T. Gigantea jewelry: the perfect alternative to Ivory.

A Giant clam history..

Here a brief description about giant clams and some valuable information about the emerging giant clam (also called Tridacna Gigas) industry in China. The Tridacna craft industry in China is fairly new. It all started in 2000 when a Taiwanese artist came to the Island of HaiNan (also called the Hawaii of China) and taught the Islanders to make sculptures, jewelry and other artifacts using giant clams. Last year (2014) the Tridacna craft market reached an estimated 600 million U$ turnover in China. Prices are quadrupling every 2-3 years as demand outdo available stock and the main industry stakeholders are now hoarding clams as Tridacnas have become a huge collectors item succeeding Jade which is found in abundance compared to Tridacna Gigas clams. In the 70ties and 80ties the giant clam was sought after as a delicacy and ten of thousands were harvested every year for human consumption. This lead to the giant clam almost becoming extinct! The few wild specimens left are now heavily protected under CITES appendix 1. The Tridacna Gigas clam is believed to be the 9th pearl of Buddha and thought to bring prosperity/good fortune and health to the owners as well as serving as a status symbol, pretty much the same as ivory. Both the giant clam and the elephants are now facing extinction because of this belief..

In Kenya the Tridacna Gigantea (a predecessor to Tridacna Gigas) only exist as fossils as they became extinct during the later Pleistocene period around 180.000 years ago when sea levels suddenly increased about 20 meters. The algae that lives in symbiosis with the clam didn't get enough sunlight, hence the clam literally starved to death because it gets up to 70% from its food delivered by the algae. There are no records of any giant clam ever having been found in the sea along the East African coast, they are all but gone..
The Tridacna Gigantea was much larger (heavier) than T. Gigas, about the double weight and it is distinctly different as it's "teeth" are somewhat rounder compared to T. Gigas. The largest T. Gigas in the world was found off the Japanese Island of Okinawa in 1956 and is currently being displayed at the Natural History Museum of Dublin, weighing 300 kg. The biggest clam in my collection weighs a staggering 612 Kg, almost twice!
It needs to be pointed out that the T. Gigantea is much rarer, only 10 to 15 clams are found every month in Kenya while thousands of T. Gigas are still found in the South China Sea every month, leftovers from the meat-harvesting during the 70ies and 80ties. As such, prices are expected to supersede T. Gigas. A double T. Gigas can cost as much as 6-10000U$ while a fossil T. Gigantea was sold for 18000£ recently (28000U$)
and a smaller size fossil T. Gigantea clam (60kg) was recently sold by Bonhams auction house for 4000 U$.
It needs to be pointed out that these clams are considerable more sought after and expensive in China compared to the US although they are becoming more and more popular as collectors item both in the US and Europe. One client from Austria bought 20 T. Gigantea from us in 2012 and sold them on to China last year, tripling his money, a good investment as these clams continue to increase in value.
Some single T. Gigas clam shell carvings sell in excess of 20.000 U$ (see photos below)

I have been collecting these fossil clams since 1999 and over the years I have managed to collect some amazing clams.
My dream was to one day find a pearl in one of these clams, not an easy task as they have to be hacked out of the surrounding limestone, not to mention; they are full of limestone on the inside as well. I know of two occasions where the worker actually destroyed pearls, mistaking them for "coral rock"! It hurst seeing a pearl broken into pieces, trust me..
In July 2015 my perseverance paid off as we finally found a cluster pearl (2pearls next to each other!) inside one of the biggest clams ever found! Roughly the size of an apple, it is without doubt one of the largest T. Gigantea pearls ever found, as far as I know; it's the only one ever found! Considering that the world's largest pearl (which was found inside a T. Gigas) "Pearl of Allah" is valued at 50 million U$ it will be interesting to have it upraised.

The work involved finding T. Gigantea, removing them, clean and polish them takes up to 2 month but a worker gets a years salary (sometimes more depending on the quality of the clam) when he finds one. It all started off as a community project and over the years we have invested millions of Ksh into some of the poorest communities along the coastline, empowering them financially.
According to Chinese beliefs that Tridacnas bring prosperity, good fortune and health, I must concur as everyone involved with T. Gigantea has had a life-changing experience (for the better) I think that more than a billion Chinese can't be wrong, do you?

Photo1. A lucky man! After month of hard work a double giant clam has been found. After selling this clam to us the man was able to buy a cow, a total of 300 cows are now roaming around Waa location and providing much needed milk for their children. Our charity is also supporting an orphanage and local schools. "No one can do everything but everyone can do something"

Photo 2. The BIGGEST clam in the world! Was found in Tiwi area in Kenya in 2010. It weighs a staggering 612 Kg!!

Photo 3. Tridacna craft/art in Hainan was exceeding 600 million U$ in 2014.

Photo 4. Tridacna art and jewelry is in high demand. Our fossil clams offer an excellent alternative to ivory and will hopefully stop poaching of our elephants as well as the harvesting of live T. Gigas from the sea!

Comments for The world's biggest giant clam is NOT Tridacna Gigas!

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Nov 15, 2015
Tridacan Gigas Clam Shell????
by: JennD

I have a very unique (to me) clam shell that was in my back yard when I bought my house many years ago. It was always fascinating to me, but it is weathered an I am finding myself always wondering about it. I could use some expertise on the matter. I want to clean it up, but don't want to do anything to damage it. It is about 27" and weighs 56lbs. If anyone out there would contact me, my email is Thanks!! Jenn

Oct 12, 2015
Fossilized clams
by: Giant Clam Fossils


To be honest the almost 3 meter clam was dug out over 20 years ago when the quarry was still early stages.. Our diggers sold it before we came.. We tried tracing back the buyer no luck it's been so long.. our diggers lack the equipment to successfully extract any fossilized pearl all they use are chissel.. Most of the pearls have been damages nd craved out.. Before we knew these diggers., they didnt know those pearls were odd shaped.. They were expecting perfectly round pearls.. The indication that there are pearls inside these clams can be seen when they partially carved out the content you will see limetone matrix inside then a calcified round shaped content.. But then the limeton is as hard as cement covering the pearls how do you extract it wihout damaging.. There are other buyers from our source and some of the bigger finds are being bought by other buyers.. Last week several 114+ cm clams were excavated and time to time there are clams over 150+ cm if anyone is interested they should reserve it will take thought.. But we are working on other intact location where there are big specimens.. Our problem is transportation it a small island without adequate transportation.. Our source has claimed that there are lots of 140+ cm clams sticking out of the mountains and thre are bigger.. I have been told.. How do you move such a heavy clam out without heavy equipment on an island.. If anyone can offer a nice price i will finance the extraction buyer can come and inspect the specimen.. Regarding the clams on our website.. They are small compared to what is out there.. It's a budget issue i only bought these speimens to put on our store.. The bigger clams are still to expensive to acquire.. But if we manage to sell some we will be able to buy bigger clams.. Other buyers from the quarry offer higher prices so we wont be able o get our hands on those.. Regarding the lam with possible pearl.. From all the clams weve seen our diggers damaged the pearls due to lack of knowledge and tools.. They only use chissel and hammer to remove the matrix.. There are those that contain pearl but there are those that doesnt thats why the description is "possible pearl" but the pearls are just to calcified to recognize.. If you manage to extract one successfully.. Best regards

Oct 12, 2015
A 3 meter fossil clam?!
by: Anonymous

A 3 meter Gigas you claim?! I only saw clams of 90cm on your website, would love to see some photos of a real big one, surely you must have taken some photos and weight? Regarding the double clam with a "possible pearl" on your website, how do you know this, did you X-ray the clam? Have you ever found a pearl? If yes, what size? Looking forward hearing more!
Best wishes,


Oct 11, 2015
Fossilized Giant Clams For Sale
by: Giant Clam Shell Fossils

The picture is a tridacna paired shell.. that's why it looks so big.. here in the Philippines we found a 20 million years old Fossilized Tridacna Gigas measuring almost 3 meters a bucket loader or Payloader had to carry it out of the Quarry and it almost didn't fit the mouth of the loader which is 3 meters in width.. we have steady source of giant clam fossils but rage from small to as almost 2 meters 3 meter long shells are out there but rarely.. if you want to buy Giant clam fossils please go to: Our prices are the lowest cause we are direct source unlike others selling them for thousands to ten of thousands of dollars for each shell

Aug 05, 2015
1,349 Pound Shell
by: Kari

It is hard to imagine a 1,349 pound shell, even if there is a photo of it...still hard to wrap ones mind around a shell being that big and then to realize it was found buried in the ground is a double hard realization. I'm glad someone has been finding these and has the ability to polish and preserve them. Also, it's nice to be free from CITIES regulations and have the freedom to sell and promote them. I'm very pleased that you took the time to share in information on my site. Thanks!

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