A question that I get alot when I conduct guided tours around our giant clam hatchery – Can they produce pearls? Indeed they can! Although not widely well-known, giant clams are capable of producing pearls of various sizes. The process of pearl formation is similar to those of oysters, where a particle acting as a ‘nuclei’ becomes the seed where new layers of material form over it, giving rise to the ‘pearls’. However, giant clam pearls are not coated with nacre (or ‘mother of pearl’) material that does not give it the similar shine and luster of conventional pearls. What’s also unique (and not surprising) is the size of the pearls produced by the giant clams – the Tridacna gigas has been found to produce very large pearls (in fact, the largest pearls in the world too!).

Here’s what I found online about the large ‘pearls’ produced by the giant clams.

Story 1: “A Large Baroque Tridacna gigas (Giant Clam) pearl

Although this story is pretty recent, the pearl (inset) was actually found within a Tridacna gigas of Papua New Guinea in 1981! Not your conventional pearl eh?

This giant clam pearl was recovered from a huge Tridacna gigas mollusk in Papua New Guinea. Photo by Lai Tai-An Gem Lab.

Story 2: “Pearl of Allah – Pearl of Lao Tzu

This is the first pearl that I was aware of – the Pearl of Allah or some called it the Pearl of Lao Tzu. The webpage has an interesting account of how the pearl got its names, as well as its origins. Although this pearl is nothing like the usual pearls – lacking the luster and iridescence – it was estimated to worth at least $3.5 million!!! \O.O/ I also found an interesting account by the man who discovered this pearl – Wilburn Dowell Cobb. Apparently, the poor diver who retrieved the pearl died in the ‘hands’ of a giant clam! What a history behind this awesome pearl…! Read on to find out more.

Doesn’t it look like a brain!? Photo credits – Website link inset.

Story 3: “Palawan Princess = 2nd largest baroque pearl

Although her story is not as exciting, gemologists and biologists are now questioning how long does it take for the clam to produce such a massive pearl? No one really knows the answer to this. My little experience with some shells we have on the hatchery tells me that the growth of ‘pearls’ is not related to the growth of clams – some large shells only have a very small ‘pearl-like’ protrusion.

The “Palawan Princess”. Photo credits – Website link inset.

So much more to learn about the giant clams! I hope that this post has enlightened you, as much as I have. 🙂