Polished Stromatolites Banded Iron Deposit
Geological Time: Very Late Archaean, 2.5 – 2.6 Billion Years Old
Size: Stromatolite is 250 mm by 180 mm, 9 mm thick (maximum)
Fossil Site: Ord Ranges, Pilbara Region, Hammersley Province, Western Australia
Fossil Code: DS18050
Price: Sold
 Description:
A polished section of what is termed locally “Tiger Iron”.
Known as Jaspelite, it is a banded structure of Tiger Eye, Red Jasper,
and Hematite. Stromatolites are remnants of the most ancient of colonial
organisms. Stromatolites are fossils that are the result of the work
of simple blue-green “algae” or Cyanophytes, which lived
in chains or mats covered in a jellylike substance. By taking in carbon
dioxide as a food source, the precipitate limy deposits on the jelly
that builds up in layers. Thus these organisms build up stony supports
for their colonies. These mound like structures can be anywhere from
several centimeters to several meters in height. The production of
oxygen is thought to have led to the “rusting of the seas”
which brought about deposition of extensive iron deposits such as
the Mesabi Range. Hematite is an iron mineral, and is one of the components
of this banded structure (dark bands). Stromatolites have persisted
to the modern day in such places as Shark Bay, Australia where they
continue their billions of years old lifestyle. This one is quite
large with the display surface having been given a high polish to
show off the myriad of colors (last photo shows the unpolished side)..
While this piece would make a fine present for any natural history
buff, anyone who appreciates art would also be glad to get thus wonderful
specimen as a gift. |
