Name 1
NATIVE MERCURY
Name 2
/
ID number
002.18.Idrija
Manager / Administrator
Idrija Mercury Heritage Management Centre
Ownership
Public
Owner
Republic of Slovenia
Local / Original ID Number
314 M–2, (vzorca M–2/1 in 2/2)
Type of Object
Ore deposit

Description

Short description
Native mercury drops in larger quantities are concentrated in pyrite-marcasite concretion (nodules) in carbon slate. The nodules are soaked with cinnabar. In carbon claystone, mercury is dispersed in the form of microscopic drops, which are gathered in larger drops on fault plates and measure up to 3 mm in size. Native mercury is impressed in the rock under pressure, therefore it constantly slowly streams out of the rock in shape of drops. The collection has 7 similar samples recorded.
Measures
/
Materials
Slate claystone with native mercury and cinnabar mould superficial layers.
Dating
Native mercury mineralisation took place approximately 238 million years ago, in the second hydrothermal phase of Mid-Triassic tectonic period.
Author / Producer
/
Picture attachments
Original use
The creation of epigenetic mineralisation with native mercury in Idrija ore deposit is not yet fully explored. It is connected with the second tectonic period at the end of the Ladinian, which was accompanied by great volcanic activity. Due to mercury overflow and lack of sulfur, cinnabar could not be formed, therefore mercury was deposited from Hg vapours and is stored in the Idrija ore deposit in economic quantities. Most often, the native mercury occurs in carbon slate claystone, in pyrite lenses and nodules, in Scythian oolitic limestones and in Skonca beds. Because of the silver drops, the miners called the slate with native mercury: silver slate or slate ore.
Present use
The sample with native mercury 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 “Minerals of Idrija ore deposit” of the Mine Geological Collection, displayed in the CUDHg administrative premises, as a part of the Francis’ shaft. In its natural environment, native mercury can still observed on several locations in the museum part of the Idrija pit in Anthony's Main Road (under the blind shaft no. 20, on the level I/20 of the Kropáč MF carbon slate is mineralised with mercury drops, in the decline I/20 - I/19 of the Kropáč MF, on the left and right side, the Skonca beds are richly mineralised with native mercury).
Original location
Idrija ore deposit, Karbon MF, III/4.
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];
- Vidrih, Renato, Mikuž, Vasja, Peljhan, Martina, Klemenčič, Tomaž. Minerali idrijskega rudišča. Proteus, 57/7, 1995, p. 269‒276;
- Vidrih, Renato, Mikuž, Vasja. Minerali na Slovenskem. Ljubljana: Tehniška založba Slovenije, 1995;
- Rečnik, Aleksander. Minerali živosrebrovega rudišča. Ljubljana: Institut "Jožef Stefan"; [Salzhemmendorf]: Bode, 2012.
Submitted
Mestni muzej Idrija
Submitted by
Miha Kosmač
Date Submitted
28. 2. 2018
Date Edited
Never