A Geoscience Digital Image Library

TitleOkenite geode in basalt, Bombay, India
DescriptionThis is a sample of basalt with needly clusters and “cottonballs” of okenite crystals grown in a vug. Okenite (hydrated calcium silicate hydroxide) is an unusual mineral and a member of the tobermorite mineral group. It is most often found in basalt vugs but has also been reported from carbonate rocks at Crestmore, California. Typical associated minerals are zeolites, apophyllite, gyrolite, calcite, quartz and prehnite. When vugs in volcanic rocks are lined with delicate okenite they are sometimes called “okenite geodes”. This sample is 21 cm across.
LocationIndia. Near Bombay.
PhotographerDarla Sondrol. 2001-06-28.
CollectionUniversity of North Dakota Mineralogy Collection.
Key wordsokenite, geode, India
Tech details681 KB. Hand specimen. Fujifilm FinePix S1Pro digital camera; 60mm AF Nikon micro lens.
GeoDIL number938