Mintabie Opals The Mintabie opal fields have been producing good consistent opal as well as nearby Lambina opals fields. In 1976 large earth moving equipment was bought in to work the opal fields Bulldozers to Bobcats and vacuum hoists replaced wheel burrow mines This area of south Australia produces good crystal opal with its unique fire and colour contrasts ,they also make beautiful triplets from this crystal opal and opalised fossils are also found in this area