I, THE HONOURABLE SIR GUY STEPHEN MONTAGUE GREEN, Companion
of the Order of Australia, Knight Commander of the Most Excellent Order
of
the British Empire, Commander of the Royal Victorian Order, Governor
in and over the State of Tasmania and its Dependencies in the Commonwealth
of Australia, in exercise of the Royal Prerogative, and acting with
the advice of the Executive Council, do by this my Proclamation, declare
that the mineral lead chromate PbCrO4 known as CROCOITE be adopted
as the Mineral Emblem of the State of Tasmania.
GIVEN under my hand and the Seal of the State of Tasmania
at Hobart
this fourth day of December, Two thousand.
G.S.M. GREEN, Governor
By His Excellency's Command,
J.A. BACON, Premier
Description
Crocoite
(lead chromate PbCrO4)
Specimens of the relatively rare mineral Crocoite from Tasmania are
displayed in Museums and Educational establishments throughout the
world. Specimens of the mineral are regarded by most mineral collectors
as being amongst the most beautiful objects to originate underground,
and to be amongst nature's most brilliant creations.
Crocoite which is composed of lead, chromium and oxygen has a minor
value as an ore of lead or chromium but is highly valued in its natural
state for the beauty, orange red colour and shape of its needle like
crystals. The metal chromium was first discovered in crocoite in 1797.
Although crocoite was fast discovered near Beresov, in the Ural Mountains
in Russia, in 1763, and has since been found in a number of other locations,
it is in Tasmania that the largest, best quality and most abundant
specimens are found.
Crocoite was first observed in Tasmania at the Heazlewood. silver
lead mine in 1895 and discovered at Whyte River, Magnet and at Dundas
shortly after.
Crocoite is now rarely seen from the Heazlewood and Whyte River areas.
At Magnet fine prismatic crystals 5 cm and longer occur in the gossan,
some associated with the yellow 'chrome' cerussite.
It is in the Dundas area, some 10 kilometres from Zeehan, that the
best and most plentiful specimens of crocoite are found. There, particularly
in the Adelaide and Red Lead mines, brilliant crystals, up to 10 cm
or longer, commonly occur freely growing on the walls of cavities.
Early in the 20th century the Adelaide mine provided large quantities
of crocoite for the Zeehan smelter where it was used as a flux.
Crocoite crystals have been mined at Dundas for over a 100 years and
the field still supplies most of the world's demand for this exquisite
mineral.
Some of the best specimens ever found are on permanent display in
the 'Mihajlowits Room' at the Zeehan Mining Museum where the mineral
is featured prominently.
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