Stunning, 17" Polished Mookaite Jasper Slab - Australia

This is a large, 17" wide polished slab of vibrantly colored mookaite jasper from Australia. The side has been polished to a glossy finish and it's accompanied by a metal display stand. There are natural fractures running through the material that have been stabilized on the backside of the slab. The spectacular display piece.

Mookaite jasper is a stunning, multi-colored stone with vibrant hues of reds, yellow and purples, formed from the fossilized remains of microscopic radiolarians. It is found in the 110 million-year-old Windalia Radiolarite formation, which formed on a shallow, marine shelf. Mookaite is found as vibrantly colored nodules in certain beds of soft white clay within the formation.

Radiolarite is a fine-grained, chert-like sedimentary rock composed predominantly of the microscopic remains of radiolarians. Radiolaria are tiny (100 micrometers!), free-floating, zooplankton that produce intricate mineral skeletons made of silica. When the radiolarians died, their tiny silica based skeletons settled on the bottom of the ocean and became covered in sediments like mud and clay.

As this sediment turned to sedimentary rock in a process known as diagenesis, the silica from the radiolarian skeletons pinched and coagulated into ribbons, nodules and other irregular concretions. These ribbons, nodules, and concretions are the mookaite within the clay layers. The coloration is due to other (mostly iron based) mineral impurities present along with the silica. Thus, mookaite can be considered as a fossiliferous sedimentary rock made out of the tiny skeletons of radiolarians.
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DETAILS
SPECIES
Quartz var. Jasper
LOCATION
Mooka Creek, Gascoyne Junction, Western Australia
FORMATION
Windalia Radiolarite
SIZE
17 x 10.2, .75" thick
CATEGORY
SUB CATEGORY
ITEM
#124247