Trégarantec, Mellionnec, Guingamp, Côtes-d'Armor, Brittany, Francei
| Regional Level Types | |
|---|---|
| Trégarantec | Mining Concession (Abandoned) |
| Mellionnec | Commune |
| Guingamp | Arrondissement |
| Côtes-d'Armor | Department |
| Brittany | Region |
| France | Country |
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Latitude & Longitude (WGS84):
48° 10' 30'' North , 3° 19' 59'' West
Latitude & Longitude (decimal):
Type:
Mining Concession (Abandoned) - last checked 2026
Deposit first discovered:
1958
Köppen climate type:
Nearest Settlements:
| Place | Population | Distance |
|---|---|---|
| Mellionnec | 463 (2016) | 2.8km |
| Plouray | 1,105 (2016) | 5.1km |
| Lescouët-Gouarec | 197 (2016) | 6.8km |
| Rostrenen | 4,011 (2016) | 7.0km |
| Glomel | 1,535 (2016) | 7.1km |
Other/historical names associated with this locality:
Château of Trégarantec
The Trégarantec uranium occurrences (in the commune of Melionnec). Among the ten or so occurrences identified, the most significant was located by Mr. Joseph Chenu on March 24, 1958, just south of the Château de Trégarantec. It consists of an intra-granitic vein zone—sub-vertical and trending N40°W—with a width of approximately 2 meters. This zone is traversed by at least three red silica veins that are locally heavily mineralized with gummite and autunite, yet do not appear to extend beyond a depth of 7 meters—the maximum depth reached during an excavation carried out in 1961.
The other occurrences, investigated via small trenches up to 3 meters deep, revealed small vein-like structures of red silica—or, more rarely, white quartz—generally showing little autunite mineralization.
Mining Concession : Locuon ("Permis Exclusif de Recherches de Locuon").
Mr. Joseph Chenu (Compagnie Armoricaine des Mines : AR. MI.), was a retired merchant seaman who, in 1957, acquired a scintillometer and prospected—specifically—the southern edge of the Rostrenen granite massif.
Benjamin CARBALLO (based on the archives of geologist Bernard Mulot)
The other occurrences, investigated via small trenches up to 3 meters deep, revealed small vein-like structures of red silica—or, more rarely, white quartz—generally showing little autunite mineralization.
Mining Concession : Locuon ("Permis Exclusif de Recherches de Locuon").
Mr. Joseph Chenu (Compagnie Armoricaine des Mines : AR. MI.), was a retired merchant seaman who, in 1957, acquired a scintillometer and prospected—specifically—the southern edge of the Rostrenen granite massif.
Benjamin CARBALLO (based on the archives of geologist Bernard Mulot)
Select Mineral List Type
Standard Detailed Gallery Strunz Chemical ElementsDetailed Mineral List:
| ⓘ Autunite Formula: Ca(UO2)2(PO4)2 · 10-12H2O References: Benjamin Carballo CollectionIdentified by Benjamin Carballo: Visual Identification, Dealer/Collection Label |
| ⓘ 'Gummite' References: Benjamin Carballo CollectionIdentified by Benjamin Carballo: Visual Identification, Dealer/Collection Label |
Gallery:
List of minerals arranged by Strunz 10th Edition classification
| Group 8 - Phosphates, Arsenates and Vanadates | |||
|---|---|---|---|
| ⓘ | Autunite | 8.EB.05 | Ca(UO2)2(PO4)2 · 10-12H2O |
| Unclassified | |||
| ⓘ | 'Gummite' | - | |
List of minerals for each chemical element
| H | Hydrogen | |
|---|---|---|
| H | ⓘ Autunite | Ca(UO2)2(PO4)2 · 10-12H2O |
| O | Oxygen | |
| O | ⓘ Autunite | Ca(UO2)2(PO4)2 · 10-12H2O |
| P | Phosphorus | |
| P | ⓘ Autunite | Ca(UO2)2(PO4)2 · 10-12H2O |
| Ca | Calcium | |
| Ca | ⓘ Autunite | Ca(UO2)2(PO4)2 · 10-12H2O |
| U | Uranium | |
| U | ⓘ Autunite | Ca(UO2)2(PO4)2 · 10-12H2O |
Other Regions, Features and Areas containing this locality
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Trégarantec, Mellionnec, Guingamp, Côtes-d'Armor, Brittany, France