Specimen #1989

Name: Bournonite (large "cogwheel") on matrix

Type: Mineral

Locality: Machacamarca Mine, near Colavi, Potosi Department, Bolivia

Favorite? N

Fluorescent? N

Size: 11.0 x 6.3 x 4.8 cm

Weight: 292

Acquired: 2010-06-17

Source: Arkenstone Auction

Label: N

Comment: Repaired - This is one of the largest "cogwheel" specimens of Bournonite that I have offered from Bolivia in the auctions. This piece hosts an attractive, sharp, tabular, very lustrous, metallic, silvery color, "cogwheel"-shaped crystal group measuring 5.1 cm (over 2 inches!) across sitting atop a matrix with Pyrite and minor associated micro Quartz. This specimen is from a find last year in Bolivia, and is certainly a big "cogwheel" not just for this locality, but any world locality.

Minerals: Bournonite (PbCuSbS₃)

There are 3 pictures on file

M01989-01.jpg:

Bournonite (large "cogwheel"), Machacamarca Mine, near Colavi, Potosi Department, Bolivia - 11.0 x 6.3 x 4.8 cm

M01989-02.jpg:

Bournonite (large "cogwheel"), Machacamarca Mine, near Colavi, Potosi Department, Bolivia

M01989-03.jpg:

Bournonite (large "cogwheel"), Machacamarca Mine, near Colavi, Potosi Department, Bolivia