Smallcleugh Mine
Also within
Condition (Natural England)
| Unit | Feature | Condition | Area (ha) | Assessed |
|---|---|---|---|---|
| NY787428 | — | Favourable | 5.01 | 2022-01-24 |
Habitats
Geology & landscape
Rock Type: Limestone
Description
Description Smallcleugh Mine lies one kilometre south east of Nenthead near the Cumbria Northumberland county boundary, some eight kilometres south east of the town of Alston. This site is selected as the largest and most detailed example of limestone flat type mineralisation in the country and is the only site for the minerals melanterite and epsomite. Extensive replacement flats in the great Limestone occur in a horst block between the northwest to southeast trending Smallcleugh Cross Vein and Handsome Mea great Cross Vein. Access is by the Smallcleugh Horse level. The limestone is replaced by ankerite, sphalerite and galena and the paragenetic sequence is admirably demonstrated. Spectacular development of mineralised cavities can be seen. Some of the cavities are large enough to walk into and are lined with cubes of galena with sides up to 30 centimetres. In addition interesting occurrences of secondary minerals including the sulphates melanterite, gypsum and epsomite have been recorded. Carrs Vein, the most important fault of the district, is exposed in the bed of the River Nent and an adjacent replacement flat in the great Limestone is the only known surface exposure of this type. The SSSI is therefore important on three counts: 1. The site has surface and extensive underground exposures of typical replacement flattype orebodies in limestone. 2. The site provides a demonstration of the relationship between structure block faulting and flat development in a specific stratigraphical horizon. 3. There are spectacular developments of the main ore minerals together with interesting secondary minerals.
Plant communities
A9 — Fast flowing river and stream, Marginal and inundation, Pond ditch and canal, Sluggish river and stream
Potamogeton natans community
Show 20 indicator speciesSchoenoplectus lacustris, Juncus bulbosus, Sparganium angustifolium, Sparganium erectum, Sparganium minimum, Alisma plantago-aquatica, Lobelia dortmanna, Equisetum fluviatile, Myriophyllum alterniflorum, Elodea canadensis, Lemna minor, Lemna trisulca, Nymphaea alba, Callitriche platycarpa, Callitriche stagnalis, Littorella uniflora, Potamogeton natans, Ranunculus trichophyllus, Glyceria fluitans, Chara subspinosa
A14 — Fast flowing river and stream
Myriophyllum alterniflorum community
Show 15 indicator speciesIsolepis fluitans, Juncus bulbosus, Fontinalis antipyretica, Lobelia dortmanna, Equisetum fluviatile, Myriophyllum alterniflorum, Lemna minor, Callitriche stagnalis, Littorella uniflora, Potamogeton filiformis, Potamogeton gramineus, Potamogeton natans, Ranunculus peltatus, Chara spp., Nitella hyalina
A17 — Chalk river and stream, Fast flowing river and stream
Ranunculus penicillatus ssp. pseudofluitans community
Show 11 indicator speciesBerula erecta, Nasturtium officinale, Elodea canadensis, Lemna minor, Callitriche stagnalis, Veronica beccabunga, Polygonum amphibium, Polygonum hydropiper, Potamogeton crispus, Potamogeton pectinatus, Ranunculus penicillatus ssp. pseudofluitans
A18 — Fast flowing river and stream
Ranunculus fluitans community
Show 12 indicator speciesFontinalis antipyretica, Fontinalis squamosa var. curnowii, Myriophyllum alterniflorum, Myriophyllum spicatum, Elodea canadensis, Mentha aquatica, Lemna gibba, Lemna minor, Potamogeton perfoliatus, Ranunculus fluitans, Glyceria fluitans, Phalaris arundinacea