Geyserite, or siliceous sinter, is a form of

opal Opal is a hydrated amorphous form of silicon dioxide, silica (SiO2·''n''H2O); its water content may range from 3% to 21% by weight, but is usually between 6% and 10%. Due to the amorphous (chemical) physical structure, it is classified as a ...

ine

silica Silicon dioxide, also known as silica, is an oxide of silicon with the chemical formula , commonly found in nature as quartz. In many parts of the world, silica is the major constituent of sand. Silica is one of the most complex and abundant f ...

that is often found as crusts or layers around

hot spring A hot spring, hydrothermal spring, or geothermal spring is a Spring (hydrology), spring produced by the emergence of Geothermal activity, geothermally heated groundwater onto the surface of the Earth. The groundwater is heated either by shallow ...

s and

geyser A geyser (, ) is a spring with an intermittent water discharge ejected turbulently and accompanied by steam. The formation of geysers is fairly rare and is caused by particular hydrogeological conditions that exist only in a few places on Ea ...

Botryoidal A botryoidal ( ) texture or mineral habit, is one in which the mineral has an external form composed of many rounded segments, named for the Ancient Greek (), meaning "a bunch of grapes".Adjective form: ''botruoeidēs'' This is a common form f ...

geyserite is known as fiorite. Geyserite is porous due to the silica enclosing many small cavities. Siliceous sinter should not be confused with

calcareous sinter Calcareous sinter is a freshwater calcium carbonate deposit, also known as calc-sinter. Deposits are characterised by low porosity and well-developed lamination, often forming crusts or sedimentary rock layers. Calcareous sinter should not be conf ...

, which is made of

calcium carbonate Calcium carbonate is a chemical compound with the chemical formula . It is a common substance found in Rock (geology), rocks as the minerals calcite and aragonite, most notably in chalk and limestone, eggshells, gastropod shells, shellfish skel ...

. In May 2017, evidence of the earliest known life

on land ''Ambient 4: On Land'' is the eighth solo studio album by Brian Eno, released in March 1982 by EG Records. It was the final edition in Eno's Ambient series, which began in 1979 with '' Ambient 1: Music for Airports''. The album was released to ...

may have been found in 3.48-billion-year-old geyserite uncovered in the Pilbara Craton of

Western Australia Western Australia (WA) is the westernmost state of Australia. It is bounded by the Indian Ocean to the north and west, the Southern Ocean to the south, the Northern Territory to the north-east, and South Australia to the south-east. Western Aust ...

Chinese Spring upper geyser basin yellowstone

References

External links

Mindat with location data
Geysers Opals Sedimentary rocks de:Sinter {{mineral-stub

See also

References

External links