We also have received some beautiful Mookaite that we are offering from $9/lb! The top chunk in the photo at right is approximately 9.6lbs and will be sold in tact. (Update - smaller piece is SOLD!) Larger piece on the bottom is under analysis for cutting into slabs or other.
Mookaite is found only in Australia and is actually a fossiliferous sedimentary rock & it is reasonably common to find cavities left by decomposed belemnite casts or in some rare cases , impressions of ammonites. (Windalia Radiolarite) Microscopic examination shows this rock consists of the remains of tiny organisms known as radiolaria that have an unusual skeletal structure of opaline silica. Billions of these little critters were deposited as sediment in the shallow areas of ancient sea beds. When the seas retreated, these sediments were cemented into solid rock by silica carried in groundwater. The type and degree of silicification varies from place to place, forming opalite, chert and chalcedony.
It has been found in many very bright colors, reds, purples, tan, snow white, ivory white, pinks and many other shades. Sometimes but not often it will have black dendrites and in the hands of a careful lapidary the cabochons can be stunning especially if you get very lucky and run into a nice dendrite tree.
No comments:
Post a Comment