Polished Stromatolites Banded Iron Deposit
Geological Time: Archean (2.7 Billion Years Old)
Size (25.4 mm =1 inch): Stromatolite is 175 mm by 155 mm (maximum)
Fossil Site: Hammersley Ranges, Mount Brockman, Western Australia
Fossil Code: AS12040
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. This one is known as Marra Mamba Tiger Eye
, and is considered the nonpareil of Tiger Eye by collectors. It
comes from only two small deposits in the Hammersley Ranges of
Western Australia. 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 natural in appearance on all but
the surface which has been given a high polish to show off the
myriad of colors. 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. |
