The microscopic photograph of the Buchak series (Paleogene) glauconite-quartz sandstone, used for the construction of the Desyatynna Church in Kyiv (10th century). Cross-polarized light, 90x
<a href="//commons.wikimedia.org/w/index.php?title=User:Monazite1982&amp;action=edit&amp;redlink=1" class="new" title="User:Monazite1982 (page does not exist)">Monazite1982</a>
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<span class="int-own-work" lang="en">Own work</span>