THE
MINERAL DUNDASITE
- Chemistry: Pb2Al4(CO3)4(OH)8 - 3H2O, Hydrated Lead Aluminum Carbonate Hydroxide.
- Class: Carbonate
- Uses: As a very minor ore of lead and as mineral specimens.
Specimens
Dundasite, which is named for the famous mines at Dundas, Tasmania, Australia where it is found, is a rare lead aluminum carbonate mineral. It is found with other lead minerals such as cerussite and crocoite. Cerussite is similar in color to dundasite but is significantly heavier. Crocoite is probably the most famous mineral from the Dundas mines and has a bright orange to red color. Together with the snow white crusts of dundasite and the striking color of crocoite, the combination makes for attractive mineral specimens.
PHYSICAL CHARACTERISTICS:
- Color is white.
- Luster is vitreous to silky.
- Transparency: Crystals are transparent to translucent.
- Crystal System is orthorhombic.
- Crystal Habits: Generally limited to crusts and small aggregates of radiating acicular crystals.
- Hardness is 2
- Specific Gravity is 3.5 (somewhat heavy for translucent minerals)
- Cleavage is perfect in one direction.
- Fracture is uneven.
- Streak is white.
- Associated Minerals include cerussite and crocoite.
- Notable Occurrences include Dundas, Tasmania, Australia and Wensley, Derbyshire and Trefriw, Gwynedd, Wales, England.
- Best Field Indicators are locality, softness, density, color and crystal habit.
 Amethyst Galleries' Mineral Gallery MINERALS |
DUNDASITE specimen dun-1
$ 60.00
$ 60.00
Dims: 1.3 x 1.3 x 0.7" (3.4 x 3.2 x 1.7 cm)
Wt: 7 g
Red Lead Mine, Dundas, Tasmania, Australia
Scores of tiny Dundasite orbs make up most of the mass of this large thumbnail piece. These orbs do not exceed 2 mm in diameter and are generally in very good condition. All are composed of crystals that are far too small to discern even with a loupe, and together they form a complex botryoidal formation. Their color is white, though some areas appear to be rust-stained, and their luster is dull and silky at best. Accompanying the orbs are sevarl small clusters of small, dark orange-brown crocoite crystals, which likely contribute to the "rust-staining" of the Dundasite.
dun-1 ($ 60.00)
Red Lead Mine, Dundas, Tasmania, Australia
DUNDASITE specimen dun-2
$ 25.00
$ 25.00
Dims: 1.44x0.79x0.78" (3.66x2.01x1.97cm)
Wt: 0.38oz (10.9g)
Zlate Hory, Silesia, Czech Republic
This specimen has numerous tiny clusters of dundasite in the form of gray to white fuzzy clusters of tiny acicular crystals. Some appear as distinct balls, while others are open, revealing their radial growth pattern. They are tiny, and thin enough that the host rock shows through, making the dundasite look darker than it really is. The host rock appears to be granular quartz with limonite, and there is more dundasite growing in the many pores of the rock.
dun-2 ($ 25.00)
Zlate Hory, Silesia, Czech Republic