Although rubies and sapphires are now over-mined around Chanthaburi , farmers have previously found gemstones while ploughing . Over 70 percent of the world's rubies have come from Thailand. Star ruby ring Examining gemstones in the host rock helps formulate the correct cutting plan. This ensures the best yield and stone shapes are obtained. Simple grinding wheels are often used in small business, which are commonly run from the owner's home.
More sophisticated operations use modern equipment such as diamond saws.
A modern facetting machine may use a diamond blade or laser to improve speed and accuracy . After cutting , the stones are sorted and graded by size and quality , with quality being determined by sparkle, colour, brilliance and the presence or absence of imperfections. Modern facetting equipment used to cut gemstones. Most gem buyers. Later the buyers arrange that cutting of the stones, often in their own workshops.