Blue clay from Cambrian of Estonia.

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Blue clay from the Cambrian of Estonia (Kunda Quarry). This clay is remarkable because it is still semi-soft and will absorb water when wet despite being approximately half a billion years old. There are some pyritized burrows visible on the rocks surface. This clay is quarried and used to make cement. Most important clay mineral in this rock is illite. Up to 2% of it consists of pyrite. The width of the specimen is 11 cm.

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Size: 4272px × 2848px
Location: Kunda, Estonia.
Photo credit: © Siim Sepp / Alamy / Afripics
License: Royalty Free
Model Released: No

Keywords: burrows, cement, clay, illite, kunda, pyrite, pyritized