Thai researchers turn rice husks, other waste into expensive gemstones
Researchers at a Thai university have found a way to turn rice husks and other farm waste into valuable ceramic gemstones, which are worth much more than the original material.
Students from Suranari University of Technology (SUT) discovered how to use agricultural waste like rice husks, straw, and sugarcane bagasse to create gemstones.
These gemstones can sell for 6,000 times more than the waste they are made from.
Saowalak Boonpakdi, one of the researchers, explained the idea behind the project. "Thailand produces a lot of rice and sugarcane. This creates waste like husks and straw, which are usually turned into fertiliser or burned, causing air pollution," he was quoted as saying.
The students studied the waste and found it contains silica, a key ingredient in natural gemstones. Using ceramic engineering techniques, they transformed the waste into gemstones through several steps.
First, the waste was heated at 300, 500, and 700 degrees Celsius to make high-quality ash. The ash was then mixed with other materials to form a chemical mixture similar to natural gemstones.
This mixture was melted at 1,300 degrees Celsius into molten glass and cooled to create a solid substance. The solid was reheated in a ceramic oven at 550 degrees Celsius to make it more durable and stable.
"The gemstone’s colour depends on the material it came from," Saowalak said. "It is strong and looks like natural gemstones, making it useful for industries."
The process adds huge value to the waste. One kilogram of husks, worth about four baht, can be turned into 20 gemstones, selling for a total of 24,000 baht.
This innovation is not only reducing waste but also creating opportunities for sustainable and valuable products.
