LIVE REPORT! 43th Nautilus Fair - Ghent, Belgium - last updated 6 minutes ago. Click here to watch.
Donate now to keep alive!Help|Log In|Register|
Home PageMindat NewsThe Mindat ManualHistory of MindatCopyright StatusManagement TeamContact UsAdvertise on Mindat
Donate to MindatSponsor a PageSponsored PagesTop Available PagesMindat AdvertisersAdvertise on Mindat
What is a mineral?The most common minerals on earthMineral PhotographyThe Elements and their MineralsGeological TimeMineral Evolution
Minerals by PropertiesMinerals by ChemistryAdvanced Locality SearchRandom MineralRandom LocalitySearch by minIDLocalities Near MeSearch ArticlesSearch GlossaryMore Search Options
Search For:
Mineral Name:
Locality Name:
The Mindat ManualAdd a New PhotoRate PhotosLocality Edit ReportCoordinate Completion ReportAdd Glossary Item
StatisticsThe ElementsMember ListBooks & MagazinesMineral MuseumsMineral Shows & EventsThe Mindat DirectoryDevice Settings
Photo SearchPhoto GalleriesNew Photos TodayNew Photos YesterdayMembers' Photo GalleriesPast Photo of the Day Gallery

Definition of acidic

1. Said of an igneous rock with a silica content above 63 weight-%
(IUGS recommendation for the classification of igneous rocks)

2. A descriptive term applied to those igneous rocks that contain more than 60% silica. Acidic is one of four subdivisions of a widely used system for classifying igneous rocks based on their silica content: acidic, intermediate, basic, and ultrabasic.

Ref: AGI

3. Applied loosely to any quartz- bearing igneous rock, usually composed predominantly of light-colored minerals having a relatively low specific gravity, especially quartz and feldspars but not feldspathoids.

Compare with: felsic
Mineral and/or Locality is an outreach project of the Hudson Institute of Mineralogy, a 501(c)(3) not-for-profit organization.
Copyright © and the Hudson Institute of Mineralogy 1993-2018, except where stated. relies on the contributions of thousands of members and supporters.
Privacy Policy - Terms & Conditions - Contact Us Current server date and time: March 18, 2018 11:24:31
Go to top of page