Home / Author Archives: David Tilley

Author Archives: David Tilley

Dr. David Tilley has a wealth of experience in the minerals industry, federal government and academia. Early in his career from 1991 to 1998 he was a PhD scholar, research associate and associate lecturer at the Australian National University, in Canberra. During this time, he lectured geology, mineralogy and field mapping techniques and studied the weathering of minerals and the formation of bauxite. From 1999 to 2005, he was a resources and energy policy writer within the Australian Government. Since 2006, he has worked as an exploration geologist for a number of exploration and mining companies in Australia and New Zealand.

Rare Earth Elements

rare earth oxides

There are 17 rare earth elements or REE for short. They include the 15 lanthanides, plus scandium (Sc) and yttrium (Y). The lanthanides are  range from the lightest lanthanum (La), ...

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Gold Deposits of New Zealand

Martha Mine, Waihi, New Zealand

Gold was one of New Zealand’s first industries. What is less known, and somewhat at odds with the countries “clean green” image, is that there are still are a number ...

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Reverse Circulation (RC) Drilling


Reverse circulation or RC drilling is a fast and inexpensive method of drilling, particularly compared to diamond drilling. A hundred metres or more of drilling is possible  a day. RC ...

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East Manhattan Wash Gold Project, Nevada

Overview The East Manhattan Wash Gold Project is a low grade high tonnage placer style gold-silver deposit. This area of wash is adjacent to and possibly overlies a zone of low sulfidation ...

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Airborne Geophysical Methods

There are a number of airborne geophysical methods used within the minerals exploration industry. Some of the most commonly used ones are aeromagnetics, radiometrics and VTEM. A digital elevation model or ...

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San Jose Mine, Mexico

Overview The San Jose Mine is located in the Taviche Mining District, Oaxaca, Mexico. The mineralization at San Jose is mainly silver with some gold, contained within epithermal veins. The ratio of ...

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Gravity Surveys

Gravity Meter. Image CC

Gravity Surveys – the basics Gravity surveys measure minute variations in gravity. Gravity at every point on the surface of the earth varies slightly depending on: distance from the equator; ...

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