Giant Clam Pearl?

(Honolulu, HI USA)

Hi,

My stepfather and I like to work with stones, shaping them into objects, taro pounders and jewelry. I used to collect giant clam shells dredged up along with seabed sediment that was used to pave roads back home. 8 years ago I collected about four hundred-plus pounds of giant clam shells and left them in my room before heading off to college. Just two months ago my mother visited me here in Hawaii, and I asked her previously to bring some clam shell slices for me to work with. With that she came with blue coral, calcite, and a giant clam pearl. I didn't believe her, but she said my stepfather was chiseling away at the inside of one of the shells, when it began to crack. So he kept chipping until much of the inner wall was removed, and he found a large nodule inside the shell wall. I've asked people in GIA and they said that it was a calcareous concretion, not very valuable, but isn't the $40 million dollar Pearl of Allah a calcareous concretion too? This nodule maybe worth a look to someone.