Provenite

Oppu Mine (Nishimeya)

MineClosedDraft data

40.4775° N, 140.2826° E · ± 1 km

Rhodochrosite from Aomori Prefecture, Japan, with photos of specimens from this locality.

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Minerals found here

Rhodochrosite

Rhodochrosite at Oppu Mine (Nishimeya)

Rhodochrosite here is mostly granular, grape-like or nodular rather than rhombohedral.

A plate of bubble-gum pink rhodochrosite from the Oppu Mine, Aomori Prefecture.
A plate of bubble-gum pink rhodochrosite from the Oppu Mine, Aomori Prefecture.
Photo: Robert M. Lavinsky · CC BY-SA 3.0 · Source
Pink rhodochrosite specimen from the Oppu Mine, Japan.
Pink rhodochrosite specimen from the Oppu Mine, Japan.
Photo: Robert M. Lavinsky · CC BY-SA 3.0 · Source
A large rhodochrosite specimen from the Oppu Mine, Nishimeya, Japan.
A large rhodochrosite specimen from the Oppu Mine, Nishimeya, Japan.
Photo: Robert M. Lavinsky · CC BY-SA 3.0 · Source
Stalactitic and botryoidal rose-red rhodochrosite covering sulfide matrix, Oppu Mine.
Stalactitic and botryoidal rose-red rhodochrosite covering sulfide matrix, Oppu Mine.
Photo: Robert M. Lavinsky · CC BY-SA 3.0 · Source
Formula
MnCO₃
Morphology
Granular, botryoidal and stalactitic crusts and nodules; well-formed crystals are uncommon
Typical size
Crusts on plates up to about 10 cm
Color / luster
Bubble-gum pink to rose-red
Associated minerals
Chalcopyritegalenasphaleritepyritequartzchlorite
Availability
No longer available
History
Known internationally among collectors as a classic Asian rhodochrosite locality

Sources: SRC-861 SRC-863 SRC-864

About Rhodochrosite →

Geology of the locality

Setting
Hydrothermal Cu-Pb-Zn(-Ag) vein deposit along faults, related to Miocene volcanic activity.
Type
Hydrothermal
Host rock
Neogene (Miocene) strata over hornfels and altered sandstone basement
Region
Aomori Prefecture
Country
Japan

Coordinates from the Japanese Wikipedia article. Mined for silver and copper since at least 1650, later copper, lead and zinc; closed 1978-1979.

Sources: SRC-861

Sources

  1. SRC-861 · Website
    尾太鉱山 (Oppu mine)Wikipedia contributors · Wikipedia (Japanese)
  2. SRC-863 · Website
    File:Rhodochrosite-118147.jpgRobert M. Lavinsky · Wikimedia Commons (dealer label)
  3. SRC-864 · Website
    File:Rhodochrosite-150445.jpgRobert M. Lavinsky · Wikimedia Commons (dealer label)

Draft data from the Provenite workbook. Check entries against the cited sources before relying on them. Photos are open-licence images from Wikimedia Commons; the author and licence are given with each photo.