Gemmants are small insects that live in caverns and mines. They look like a larger than normal ants with bodies made out of gemstone. They come in different appearances like ruby, sapphire, emerald, or quartz. Biologists researched the gemmants to discover an S E field meaning they were supernaturally evolved creatures. There is a theory that someone with magical abilities wanted to get rich, so they experimented on ants to turn them into gemstones.
One may be excited to find a gemmant while exploring a cavern. They can be caught and used like normal gemstones. The downside to using these creatures is they have a mysterious venom which, if they bite open skin, will turn the area into stone. The condition of skin turning to stone is known as stonitis. The area will not spread, but it will be a nuisance until cured. The usual treatment is an injection near the stonitis which will slowly turn the stone back to normal skin.
The saying that someone has "gemmants in [his/her/their] pants" refers to someone being very wealthy.