Please help me identify this seashell from Asia

[dave r]

By Troca shell I believe she means<i> Trochus niloticus</i>, the Commercial Trochus. This was used for many years for making buttons and yes, it is mother of pearl. Unfortunately the term 'Mother of Pearl' can mean many types of shell; freshwater mussels such as yours, <i>Trochus</i>, <i>Turbo</i>,<i> Haliotis </i>(Abalone, paua or ear shell) and some other <i>Trochidae</i>. Your friend's spoon certainly does not look like it was made from Trochus shell as it would be too curved, it does look to me like it was made from a freshwater mussel (and I am aware that these objects are being made in S.E.Asia)but it could just possibly be made from a lagre Turban shell such as <i>Turbo marmoratus</i> but it is unlikely as large specimens of this species are becoming rare and hard to get. It would be worth much more as a specimen shell.
I hope this has been helpful.
Cheers,
Dave