Kutna Hora

[CZ] Historie Kutné Hory je nerozlucne spjata s dolovanims tribrných rud. Na konci 13. stoleti, poskytovaly doly v Kutne Hore zhruba jednu tretinu evropske produkce stribra. Na prelomu 14. a 15. stoleti, mistni dul Osel dosahl hloubky peti set metru a byl ve sve dobe nejhlubsim dolem na svete. Bohatstvi plynouci ze zdejsich dolu, vedlo k rozkvetu mesta a bylo zakladem pro hospodarsky a mocenskopoliticky rozvoj ceskeho kralovstvi. Diky mnozstvi dochovanych historickych pamatek byla v roce 1995 Kutna Hora zapsana do seznamu svetoveho kulturniho dedictvi UNESCO.

Pohled na dolovani stribra z geologickeho hlediska.
Kutnohorsky region je z gelogickeho hlediska tvoren tzv. "Kutnohorskym Krystalinikem", ktere je oddeleno od Moldanubika tektonicky Ratajskou zonou. Kutnohorske Krystalinikum je tvoreno zejmena metamorfovanymi horninami jako jsou ortoruly, migmatity, svorové ruly, biotiticke ruly a take grafitickymi horninami. V prvohorach byly tyto horniny vystaveny silnym horotvornym pohybum, ktere vytvorily pukliny do kterych vnikly horke roztoky s rozpustenymi nerostnymi latkami a ty postupne vykrystalizovaly v rudne zily. Tato hydrotermalni mineralizace vedla k tomu, ze zdejsi rudne zily obsahuji primesi olova, zinku, medi a zejmena stribra.

Dulni dilo, ktere muzet navstivit je patri do tzv. Oselskeho pasma. Je razeno v rulach kutnohorskeho krystalinika. Stropy chodeb jsou tvoreny bazalnimi kridovymi slepenci. V nadlozi ruly se pak nachazi usazene horniny obsahujici vapenec, takze zde muzeme pozorovat podobne jevy jako v krasovych jeskynich. Muzeme videt napr. sintrove povlaky sten, mensi krapniky, zaclonky a brcka.

Stribro se nachazi v prirozene ryzi forme jen velmi vzacne. Nejcasteji se vyskytuje v kombinaci s obsahem siry, arsenu, antimonu nebo chloru a v ruznych rudach jako je argentit (Ag2S) a chlorargyrite (AgCl).

Zakladni typy sulfidickych rud obsahujicich stribro, lze rozdelit na tri skupiny:

• a) uslechtile rudy stribra
  jsou pomerne vzacne a obsahuji vysokou koncentraci stribra
• b) sulfidicke rudy
  smesi obecnych sulfidu, ktere obsahuji stribro v setinach procent
• c) galenitove rudy
  zde byl zpracovavan stribronosny galenit s prumernym obsahem stribra v desetinach procenta.

Ukoly pro logovani:
1. Poslete mi pres profil odpovedi na nasledujici otazky:
a) Jake je priblizne stari kutnohorskeho krystalinika?
b) Vyjmenujte alespon pet rud z kterych se ziskava stribro.
c) Zjistete, kdy byla zdejsi stola objevena a vyjmenujte alespon dve dalsi kutnohorske stoly, kde se tezily stribronosne rudy.
2. Vyfotit sebe nebo svou GPS pred vchodem do muzea. (dobrovolny ukol)

Logovat muzete ihned, pokud by byla nejaka nesrovnalost v odpovedich, ozvu se.

Odkazy a zdroje:
Virtualni prohlidka
Ceske muzeum stribra
Dolovani v Kutne Hore
D. Velebil, Hutnictvi stribra

Museum je otevreno:
duben a rijen 9.00 – 17.00
kveten, cerven a zari 9.00 – 18.00
cervenec a srpen 10.00 – 18.00
listopad: sobota, nedele 10.00 - 16.00
pondeli je zavreno.

Navsteva muzea neni k odlovu kese nezbytna, ale navstevu doporucuji, protoze prohlidka dulniho dila je opravdu zazitek :-)

[EN] The history of Kutná Hora is inseparably connected with the mining of silver ores. At the end of the 13th century, the mine at Kutná Hora was already providing about one third of European production of silver. At the turn of the 14th and 15th centuries, the local Osel mine attained a depth of five hundred metres and was the deepest mine in the world at that time. The wealth of the local mines, forming the basis for the power of the Bohemian kings, led to the building of a number of historical monuments, leading to inclusion of the city in the UNESCO World Cultural Heritage List.

Silver mining from the geological point of view.
The Kutna Hora region geologically consists of "Kutna Hora crystalline" separated from Moldanubicum tectonically by Ratajska zone. Kutna Hora crystalline consist mainly of metamorphic rocks like orthogneiss, migmatite, schist gneiss, biotite gneiss and graphitic rocks. In the Palaeozoic these rocks were exposed to the high presusure and tectonic movements. This tectonic activity formed cracks filled with hot solution of dissolved mineral substances, which later crystallized in the ore vein. This hydrothermal mineralization led to the fact that local ore vein contain additions of lead, zink, copper and mainly silver.

Mine, which you may visit belongs to the so-called Osel zone.It is minted in Kutna Hora crystalline gneisses. The ceilings of tunnels are formed by basal Cretaceous conglomerates. In the overlying gneisses you will find a sedimentary rock that consists of limestone, so you can see similar phenomenes like in karst caves. For example you can see flowstone coating the walls, small stalactites, drapery and straws.

Silver is found in native form very rarely as nuggets, but more usually combined with sulfur, arsenic, antimony, or chlorine and in various ores such as argentite (Ag2S) and chlorargyrite ("horn silver," AgCl).

Basic raw material of the metallurgic process is ore. Three groups of sulphidic ores containing silver can be theoretically distinguished:

• a) Noble silver ores
  are quite rare and contain high amount of silver
• b) Complex sulphidic ores
  mixture of common sulphides with silver content of 0.0x %.
• c) Galena ores
  silver bearing galena with silver content of 0.x %.

The necessary tasks for logging:
1. E-mail me answers to these questions:
a) What is the approximate age of Kutna Hora crystalline?
b) Please list at least five of ore from which silver is extracted.
c) Find out, when the mine was discovered. List atleast two more mines in Kutna Hora where the silver ores was mined.
2. Take a photo of you (or your GPS unit) in front of the entrance to the museum. Attach taken photo to the log.

With logging you do not have to wait for a response. If something goes wrong, I'll call.

Links and sources:
Virtual visit
Czech Museum of Silver

Museum is open:
April and October 9.00 – 17.00
May, June and September 9.00 – 18.00
July and August 10.00 – 18.00
November: Sat, Sun 10.00 - 16.00
Closed on Monday