Esfalerita Marmatita
Esfalerita is a mineral with formula (Zn,Fe)S, in the Sulfuros group. This specimen comes from Mina Lola, Portman, Murcia, Región de Murcia, España and joined the Terrium collection in 2021.
Description
Large black crystals of sphalerite (marmatite) with metallic lustre and pronounced striations, accompanied by small white calcite crystals on matrix. A specimen with strong visual contrast between dark masses and light coatings.
History of this specimen
Historic collector material that can only be seen in old collections. Aleydis rescued it in 2021 and labelled it 827C. These pieces came out in the 1980s; access was by a wooden ladder that collapsed over time, and since then absolutely nothing has come out from there.
About Esfalerita
Sphalerite is the principal zinc mineral. The variety marmatite is iron-rich, black in colour, occurring as massive aggregates or as lustrous crystals.
About the locality
Mina Lola, in Portman, was worked until the 1960s and in the 1980s became a pilgrimage site for collectors. Access was via a shaft with wooden ladders, requiring a rope descent of more than 80 m. Inside, geodes appeared lined with quartz carrying lustrous crystals of sphalerite (marmatite), sometimes with pyrite. One of the last explorers, Manuel Morales, described in detail his descents into the mine: he recalled the hardship and risk of these incursions, whole days underground, and the finding of geodes with high-quality crystals, bright and clean, unique in the Cartagena-La Unión mining range. Morales also recounted an unforgettable surprise: among remnants of explosives there were old newspapers, and one was exactly from the day of his birth, which made the experience an indelible memory. Eventually the access gallery collapsed and the landowner set fire to the ladderway shaft to prevent accidents, sealing the deposit definitively. Since then, only historic specimens remain in old collections.
Technical data
- Catalogue No.
- 0167
- Composition
- (Zn,Fe)S
- Name
- Esfalerita
- Variety
- Marmatita
- Group
- Sulfuros
- Category
- Cupidium
- Associations
- Calcita
- Mine
- Mina Lola
- District / Municipality
- Portman
- Province
- Murcia
- Region
- Región de Murcia
- Country
- España
- Size (cm)
- 7 x 6.5 x 5.5
- Weight
- 216 g
- Acquired
- 2021
- Ex-collection
- Aleydis Soliveres
- Etymology
- From the Greek "sphaleros" ('deceptive'), for its confusion with galena. The variety name marmatite derives from Marmato (Colombia), a classic locality.
- Quality
- Muy buena
- Value trend
- Estable
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