How to say 硨磲 in English?
As we know that 硨磲 in one of the seven treasures in Buddhism (佛教七寶之一), which are Gold, silver, lapis lazuli, crystal, agate, red pearl and carnelian. However, I am not sure which one is 硨磲? Also the tridacnae in wikipedia is its biological name, not English, anyone shed some light on me? Thanks a lot.
Gaint clam seems to refer the sea animal but not the gemstone.

Question

How to say 硨磲 in English?
As we know that 硨磲 in one of the seven treasures in Buddhism (佛教七寶之一), which are Gold, silver, lapis lazuli, crystal, agate, red pearl and carnelian. However, I am not sure which one is 硨磲? Also the tridacnae in wikipedia is its biological name, not English, anyone shed some light on me? Thanks a lot.
Gaint clam seems to refer the sea animal but not the gemstone.

Answer

Hello Dino Hsu,

In the original sutras (Buddhist scriptures) written in Sanskrit, the Seven Treasures are:   1. Suvarna   2. Rupya   3. Vaidurya   4. Sphatika   5. Musaragalva   6. Rohitamukta   7. Asmagarbha.
They have been translated to different Chinese terms ,that  even differed in various dynasties and to English terms as well later.
It is obvious that there are many interpretations of the Seven Treasures in Chinese and English with  same Chinese term interpreted as different substances in Western literature and the only definitive list being the original in Sanskrit. 
It seems that the 硨磲 ( giant clam) was replaced in the Western literature by Tridacna . The White Coral was replaced by Pearl / Mother of pearl / Tridacna.So your list is possibly one of the Chinese translations ,while the 硨磲 Tridacna is interpreted differently in the English translation as a gemstone.

Answer

giant clam, I hope it helps.