Abstract

Among the many mineral substances replacing the original carbonate of lime composing what are generally known under the name of "fossils," are iron-pyrites, iron-oxide, sulphur, malachite, magnesite, talc, and silica of various forms, such as Beekite, chalcedony, and both common and precious opal. By far the commonest mode of replacement is that whereby an originally calcareous skeleton is replaced by silica. This process of "silicification" – of the replacement of lime by silica – is not only an extremely common one, but is also a readily intelligible one; since carbonate of lime is an easily and flint a hardly soluble substance. It is thus easy to understand that originally calcareous fossils, such as the shells of Mollusca, or the skeletons of Corals, should have in many cases suffered this change, long after their burial in the rock, their carbonate of lime being dissolved away, particle by particle, and replaced by precipitated silica, as they were subjected to percolation by heated or alkaline waters holding silica in solution.

 
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Bibliographic Data

Short Form
Etheridge, 1893, Rec. Aust. Mus. 2(5): 74–76
Author
R. Etheridge
Year
1893
Title
On the occurrence of Beekite in connection with "fossil organic remains" in New South Wales
Serial Title
Records of the Australian Museum
Volume
2
Issue
5
Start Page
74
End Page
76
DOI
10.3853/j.0067-1975.2.1893.1197
Language
English
Plates
plate xvi
Date Published
30 September 1893
Cover Date
30 September 1893
ISSN
0067-1975
CODEN
RAUMAJ
Publisher
The Australian Museum
Place Published
Sydney, Australia
Digitized
11 September 2009
Reference Number
1197
EndNote
/Uploads/Journals/16668/1197.enw
Title Page
/Uploads/Journals/16668/1197.pdf
File size: 99kB
Complete Work
/Uploads/Journals/16668/1197_complete.pdf
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