Aventurine is a green colored chalcedony quartz that has chromium bearing platelets of a darker green color within it.
Aventurine is named after a created stone, goldstone oravventurina glass
which means "by chance" or adventure in Italian. Goldstone was created by accident with copper filings falling into 17th century Venetian glass makers molten glass. Natural aventurine has similar metallic platelets in the base stone which in gemology is now called aventuresence.
It is hard for the layman to tell the difference between aventurine and jade. The green of aventurine varies from light green to a very dark green. It's color is like the first green in a new field of grass, without pretension, but with vitality and the promise of growth. It has a calming effect on our nervous system.