Bangkok Gemstone Sourcing

Rough from mines across Africa, Asia and South America is brought to Thailand to be cut, treated and traded. The cutting expertise, the heat treatment capability and the concentration of buyers are all in the same place, which is why so much of the world's coloured stone passes through it regardless of where it came out of the ground.

The practical consequence for a buyer is choice. A requirement that would take weeks to fill from a single mine-side source can often be filled here from several, because the material is already in the market.

The coloured stone business is concentrated in the Bang Rak district of central Bangkok, around the meeting of Silom and Mahesak Roads. Cutters, dealers, brokers, treaters and gemmological laboratories sit within a few streets of each other.

Our office is on Mahesak Road, inside that district. That proximity is the whole point: a requirement can be walked around the trade rather than emailed at it, and stones can be looked at in person before anything is sent to a buyer.

Two things, mostly. The first is access — a buyer abroad cannot see what is in a dealer's safe, and much of what trades here never appears in any listing.

The second is filtering. The volume of material available is the problem rather than the solution: someone has to look at a great deal of it against your specification and reject most of it. That is the work.

The workable pattern is specification first, images and video second, selection third, pricing last. Ask for pricing before the stones have been identified and you get a range rather than a quote.

Video matters more than photographs for anything where transparency, extinction or colour behaviour under movement is part of the judgement — which is most coloured stones, and all rough.