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The Mineral Evolution database is currently under development.
The goal of this page is to present localities at which the mineral is found, and estimates of the oldest possible geologic age of the minerals at these localities.
This mineral is using an age reported as an element mineralization period.
O
This mineral is using an age calculated from all data at the locality.
R
The age displayed for this mineral originates from a different, non-child locality.
P
The age displayed for this mineral is the range of ages for this mineral at all of this locality's children.
This mineral's age has not yet been recorded.
This Mineral list contains entries from this locality, including sub-localities. Minerals in bold are reported by mindat.org as occurring directly at this locality, and do not occur at any children (sublocalities) of this locality.Elements at this locality, including sub-localities: AgAlAsAuBaCCaCdClCuFFeHHgKMgMnMoNaNiOPPbSSbSiSrTiUVZnZrElements from minerals reported directly at this locality: Al Ca Fe H K Mg Na O S Si Ti Structural Groups for minerals in this locality:
Near-surface occurrence of weddellite at a former limestone quarry. Weddellite forms as the oxalic acid from lichen interact with the limestone/calcite.
Michelle_727
Ashover-Crich anticline is associated with the uplift of the Derbyshire Dome at 280 ma. The uplift exposed the Fallgate Volcanics, Matlock and Cawdor Limestone and Cawdor Shales of Visean age, and siltstone, mudstone and gritstone beds of Namurian age.
Michelle_807
The Fallgate Volcanics is exposed by the uplift of the Derbyshire Dome. This formation was visible in the Milltown Quarry on the Northwest corner as the Fallgate Tuff but is currently buried beneath slurry from fluorite workings.
Michelle_808
The Matlock and Crawdor Limestone are of Visean age. These formations host the Pb-Zn-Fluorite veins of Permo-Triassic to Jurassic age. The formations were exposed by the uplift of the Derbyshire Dome.
Michelle_809
The Matlock and Crawdor Limestone are of Visean age. These formations host the Pb-Zn-Fluorite veins of Permo-Triassic to Jurassic age. The formations were exposed by the uplift of the Derbyshire Dome.
Michelle_810
The Cawdor Shale
Michelle_811
The Namurian age Ashover Grits include siltstone, mudstone and gritstone.
Michelle_812
Pb-Zn-Fluorite mineral vein and chimney deposits in the Milltown Quarry are concentrated on the Southeastern flank of the Ashover-Crich anticline. Mineral veins (rakes) include Blackwell, Mill, Spencers, Great, Woodhead and Lomas.
Michelle_813
The formation of zinc hydroxide minerals described here would require a highly alkaline oxidizing environment. Such an environment could have been caused locally by the leaching of calcined limestone, itself the result of lime burning or possibly of the older pre-gunpowder mining technique of fire-setting. A relationship between the formation of the zinc hydroxides and weddellite has not been ruled out. The paper refers this as the 'zinc hydroxide zone'.
Mineralization is likely of post-mining age due to the calcination of limestone interacting with zinc from vein mineralization. The reference suggests an anthropogenic origin for mineralization of the zinc hydroxide zone.
In the specimen analysed, the original ferro-magnesian minerals had been replaced by new chlorite and silica, and the plagioclase was somewhat kaolinized. The greater part of the previously accumulated radiogenic argon would have diffused from the rock during metasomatism and the age obtained is closely related to that of the mineralization (i.e., the formation of new chlorite) and not to that of extrusion.
Sample
Source Locality
Reference URL
All locality data graciously provided by mindat.org