Polished fossil Oncolite slab. ONC112 green U112 Unakite rough rock

U112 Unakite rough rock

cut and polished on one side with a natural weathered back

180 mm x 150 mm x 6

PA283  Pilbara Agate

Weighs 449 grams

Polished fossil Oncolite slab. ONC112 green U112 Unakite rough rockONC112. 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. 145 mm x 105 mm x 8 mm thick. Weighs 285 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 in