The Workhorse of The Mintabie Field.

The bulldozer is the machine of choice for recovering all of the opal in a claim.  The Caterpillar D-9 has been used extensively and is one of the main classes of dozer used to successfully rip the Mintabie sandstone.  

Scrapers:

Scrapers were first introduced to Mintabie in the early to  mid 80's and are excellent for quickly removing sand and overburden and transporting it well away from the claim being worked.  

In most circumstances, bulldozers "push-load" the scraper in order to completely fill the scraper bowl.  This also speeds up filling the bowl and saves wear and tear on the scraper.  

Excavators have been used periodically in Mintabie, but are extremely slow at penetrating and digging the Mintabie sandstone.  Some areas within the field have softer sandstone, but in the part of Mintabie pictured, the excavator was struggling and the project proceeded very slowly.