Polished fossil Oncolite slab. ONC114 beryl MN132 Magneprase slab

MN132  Magneprase slab

KO106  Killaloe Opal slab

CW132   Chinese Writing Stone rough rock

100% natural

DO173  Dendritic Opal slab

Polished fossil Oncolite slab. ONC114 beryl MN132 Magneprase slabONC114. Fossil Oncolite polished slab. From the Miocene "Trealla Limestone" north of Carnarvon, Western Australia . Age is approx. 15 million years. Dimensions at widest points approx. 150 mm x 100 mm x 7. 5 mm thick. Weighs 241 grams. Oncolite is a limestone composed largely of oncoidsrounded, coated grains that grow as thin layers of lime mud accumulate around a tiny nucleus (such as a sand grain or shell fragment) under microbial influence. Formed