Name 1
MINERALISED DOLOMITE CONGLOMERATE
Name 2
/
ID number
002.31.Idrija
Manager / Administrator
Idrija Mercury Heritage Management Centre, Bazoviška 2, SI-5280 Idrija
Ownership
Public
Owner
Republic of Slovenia
Local / Original ID Number
RE– 39, 571
Type of Object
Ore deposit

Description

Short description
The sample of grey dolomite conglomerate is transected and polished. It is composed by unsorted, different sized dolomite gravel-stone with kaolinite and dolomite sandy base. The conglomerate is covered with veins and moulds of superficial cinnabar layers. Some gravel-stones were probably mineralised when flooded int the sedimentation environment.
Measures
Length 16cm, width 12cm, thickness 6cm.
Materials
Dolomite conglomerate
Dating
Triassic, Ladinian – Longobardian.
Author / Producer
/
Picture attachments
Original use
The described sample is a characteristic specimen of epigenetic mineralisation in the Idrija ore deposit. The central part of ore (Karoli tectonic unit) was, in the second erosion phase, filled dolomite breccias with clay-muddy binder and gravel with kaolinite-dolomite sand binder in the lower and middle part, and with dolomite conglomerate in the upper part. At the end of Ladinian, the volcanic and hydrothermal activity increased. The rocks next to the faults and cracks were, in different intensity, substituted with cinnabar, so that the variants of rich and poor cinnabar ore were formed. Mineralised gravel-stone of Upper-Scythian dolomite was flooded as gravel-stone in the middle part of the Karoli tectonic unit. Later on, the gravel sample with gravel-stone of older mineralisation was additionally hydrothermally poorly mineralised with cinnabar.
Present use
The mineralised dolomite conglomerate is being preserved, secured and presented as important natural heritage of Idrija ore deposit with exceptional universal values. It represents a unique soil “archive”, as the sample was excavated in Idrija ore deposit and also stored. It is a part of the thematic collection “Epigenetic ore” of the Mine geological collection, displayed in the administrative premises of CUDHg, as a part of the Francis’ shaft. It can be used for temporary exhibitions and for other types of mercury heritage promotions.
Original location
Idrija ore deposit, Logar MF
Present location
CUDHg (Mining Geological Collection), Bazoviška 2, SI-5280 Idrija

STATE OF CONSERVATION

History of conservation:
The sample is appropriately preserved. Additional interventions are not necessary. Security of the premises is taken care of.
Present state
good
Necessary activities:
Regular seasonal maintenance.

DOCUMENTATION

Addresses / collections / links etc. where further in-depth information is accessible:
- CUDHg Inventory Book;
- Čar, Jože. Rudniška geološka zbirka: Seznam in opis vzorcev. Mercury Mine Idrija, 2003, p. 1–122, [material is kept in the CUDHg archive];
- Čar, Jože. Razvoj srednjetriasnih sedimentov v idrijskem rudišču: doctoral thesis. Faculty of Natural Sciences and Engineering in Ljubljana, 1985;
- Drovenik, Matija, Mlakar, Ivan. Strukturne in genetske posebnosti idrijskega rudišča. Geologija, 14, 1971, p. 67‒126.
Submitted
Mestni muzej Idrija
Submitted by
Miha Kosmač
Date Submitted
1. 3. 2018
Date Edited
Never