Kyanite from
Groppera Alp, Madesimo, Sondrio Province, Lombardy, Italy
Locality type: | Mountain | |
Classification | ||
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Species: | Kyanite | |
Formula: | Al2(SiO4)O | |
Comments: | http://www.mindat.org/forum.php?read,105,308669,364058#msg-364058 In my opinion the mineral Kyanite has been added without any valid justification or by mistake. Because: 1) the reported bibliographic reference "(Brugger J. (1996): The Fe, Mn, (V, Sb, As, Be, W) deposits of Val Ferrera (Graubünden, Switzerland). Unpublished PhD Thesis, Univ. Basel. 188 p." has nothing to do neither with the locality nor with the paragenesis in question. 2) I personally surveyed both Alpe Groppera and Torrente Scalcoggia collecting sites several times since their discovery in 1984, never observing any trace of kyanite, especially in macroscopic samples. 3) the posphates are hosted both in quartz rich layers and in mica rich layers of what appears to be a "low (green schists ?) metamorphic grade" meta-pelite \ meta-psammite interpreted to be part of the oldest (permo-triassic ??) sedimentary cover of the Suretta Nappe. Although not impossible the occurrence of Kyanite in such contest would be unsual, In addition the occurrence of pyrofillite at Torrente Scalcoggia is not in favour of the co-occurence of Kyanite (pyrophillite is replaced by Kyanite (or Andalusite) + Quartz at temperature higher than about 400°C. I am not saying that is impossible to found some Kyanite, even in macroscopic samples not far from the described sites. That's because rock masses belonging to the "hercinian basement" outcrop not far from both sites. | |
Confirmation | ||
Validity: | Erroneously Reported | |
Data | ||
Mineral Data: | Click here to view Kyanite data | |
Locality Data: | Click here to view Groppera Alp, Madesimo, Sondrio Province, Lombardy, Italy | |
Data Identifiers | ||
Mindat Occurrence Record ID: | 822037 | |
Long-form Identifier: | 1:3:822037:0 | |
GUID (UUID V4): | afe0c86a-9113-4040-81af-6be498a3b965 | |
Nearest other occurrences of Kyanite | ||
15.2km (9.5 miles) | ⓘTrescolmen whiteschist outcrop, Mesocco, Moesa Region, Grisons, Switzerland | |
15.5km (9.6 miles) | ⓘTrescolmen quartzite outcrop, Mesocco, Moesa Region, Grisons, Switzerland | |
15.5km (9.7 miles) | ⓘCima di Gagela, Mesocco, Moesa Region, Grisons, Switzerland | |
16.9km (10.5 miles) | ⓘAlpe di Boggio (Alp de Bec), Soazza, Moesa Region, Grisons, Switzerland | |
18.4km (11.4 miles) | ⓘCasnaggina Valley, Villa di Chiavenna, Sondrio Province, Lombardy, Italy | |
18.9km (11.8 miles) | ⓘGarzelli Valley, Bodengo Valley, Sondrio Province, Lombardy, Italy | |
19.8km (12.3 miles) | ⓘZapporthorn whiteschist outcrop, Mesocco, Moesa Region, Grisons, Switzerland | |
20.3km (12.6 miles) | ⓘRebolgin Valley, Lostallo, Moesa Region, Grisons, Switzerland | |
22.2km (13.8 miles) | ⓘPromegn, Cama Valley, Cama, Moesa Region, Grisons, Switzerland | |
24.4km (15.1 miles) | ⓘArvigo, Calanca, Moesa Region, Grisons, Switzerland | |
References | ||