This presentation box holds 24 Indian zeolite specimens side by side. They differ in colour, surface and crystal shape, so a single box shows how varied zeolites can be. It measures about 31 × 31.5 cm and is 4 cm deep.
A stone that gives off steam
Axel Fredrik Cronstedt, a Swedish mineralogist, named zeolite in 1756. He noticed that when he heated it, steam rose from the stone as if it were boiling. The name joins two Greek words meaning to boil and stone.
Zeolite is the name of a whole mineral family, with dozens of known members. That is why one box can hold so many different colours and shapes. Man-made zeolites are used today in some washing powders, to soften the water.
From India's basalt
Zeolites grow mainly in the cavities of volcanic rock such as basalt. Western India sits on a vast sheet of basalt, and the country is one of the world's best-known sources of zeolites. These specimens also come from India.
For a collection or a classroom
The box is a ready-made small collection. You can keep it in a glass cabinet or on a table where guests can look at it. In a school lesson or a club, it shows how the members of one mineral family look side by side. It makes a good present for someone just starting a collection. Placed near a window, the crystals catch the light from the side and their shapes show up better.
The pieces are natural and the selection differs from box to box, so the photo is only an example. Handle the fine crystals gently, as they are fragile, and keep them away from small children.