Page 70 - Handbook of Gold Exploration and Evaluation

Nature and history of gold 51

containing fossils. He observed that the same fossil types were specific to the
same strata both locally and further afield. In 1815 he published the first
geological maps showing the strata of England.
In 1830 Charles Lyell completed the first volume of a three-volume textbook
called Principles of Geology. He began a study that showed the Earth to be at
least several hundred million years old and two years later he identified the
Recent, Pliocene, Miocene and Eocene periods of Earth history. Charles Darwin
(1844) confirmed Lyell's work from geological observations on volcanic islands
visited during the voyage of HMS Beagle, as being equally applicable to places
that Lyell had never visited. He is remembered particularly for his part in the
development and acceptance of a standard geological time scale based upon the
presence of characteristic fossils in the rock.
In 1871 Dmitri Mendeleev asserted that `the properties of elements are in
periodic dependence upon their atomic weight'. The gaps in his periodic table
represent undiscovered elements, which were filled by discoveries of new
elements in 1875, 1879, and 1885.

1.2.7 Great gold rushes of the 19th century

The plundering of gold and destruction of the Inca and Aztec civilisations by
Spanish and European financial and religious adventurers promoted a worldwide
search for fortunes that could be gained by digging for gold in new unexplored
areas. Locations of the great gold rushes of the 19th century are shown in Fig.

1.17 Locations of the great gold rushes:
1, California; 2, Klondyke; 3, New South Wales 4, Victoria; 5, Otago; 6, West
Coast; 7, Queensland; 8, Western Australia; 9, Transvaal. Also shown are some
of the main sources of gold found during the 20th century (after Nolan, 1980).