This very special variety of quartz gave the name to the same property it shows. This is due to mainly the small mica inclusions, in some cases, other inclusions changes the color and we will get yellow, brown, blue or green aventurine. Technical/details SiO2 - Silicon Dioxide This form of Crypto crystaline Quartz contains inclusions of small crystals that reflect light and give a range of colors - depending on the nature of the inclusion. Hence aventurine may be green, greenish-brown, bluish-white, bluish green and orange. Aventurine claim to fame is having inclusions that look like sparkles. Extremely high quality aventurine (without the inclusions), looks like an Emerald. Colors: Green, greenish-brown, blueish-white, bluish green and orange. Care and Treatment:Aventurine has been confused with Amazonite and Jade. Dark green Aventurine generally has inclusions (due to green fuchsite mica and perhaps a bit of pyrite) which creates a speckled appearance. Aventurine, it is usually assumed to be green if a color is not associated with it.