opaliikivi

Opaliikivi is a type of volcanic rock that is primarily composed of opal, a form of silica. It is known for its iridescent play of colors, which can range from shades of red, orange, yellow, and green, to blue and purple. This unique color display is due to the presence of opal, which is a hydrated amorphous form of silica. The opal within opaliikivi often forms in small, spherical inclusions or as thin layers within the rock.

Opaliikivi is typically found in volcanic regions, particularly in areas where volcanic activity has occurred. It is often associated with rhyolite, a type of volcanic rock that is rich in silica. The formation of opaliikivi is a result of the interaction between silica-rich volcanic gases and water, which leads to the precipitation of opal within the rock.

The term "opaliikivi" is often used in the context of Finnish geology, where it is a common type of volcanic rock found in the country's numerous volcanic fields. It is also known by other names in different languages, such as "opalite" in English and "opalit" in Swedish.

Opaliikivi is not only valued for its aesthetic appeal but also for its potential use in jewelry and as a decorative stone. Its unique color play and the fact that it is a volcanic rock make it a fascinating subject for geologists and collectors alike. However, due to its rarity and the fact that it is often found in remote volcanic regions, opaliikivi can be difficult to obtain and is therefore relatively rare in the market.