Mispickle Arsenopyrite Brandy Gill Cumbria UK Iron Arsenic Sulfide Specimen

Genuine Mispickle (Arsenopyrite) – Brandy Gill, Eden, Cumbria

This Mispickle, more formally known as Arsenopyrite, from Brandy Gill in the Eden district of Cumbria, UK, is a genuine British mineral specimen carefully selected for quality, crystal character and historic locality. The photograph provided shows the exact specimen you will receive. Please refer to the images for full sizing and scale details.

Your crystal includes a Certificate of Authenticity lifetime guarantee generic card confirming its genuine mineral identity and documented Cumbrian provenance.

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Mineral Species & Crystal Structure

Arsenopyrite is an iron arsenic sulfide mineral with the chemical formula FeAsS. It belongs to the sulfide mineral group and crystallises in the monoclinic crystal system.

Mineral Name: Arsenopyrite (Mispickle)
Chemical Formula: FeAsS
Mineral Group: Sulfide
Crystal System: Monoclinic
Hardness: 5.5–6 on the Mohs scale
Lustre: Metallic
Colour: Silver-white to steel-grey

Arsenopyrite commonly forms prismatic, columnar or bladed crystals, often with striated faces. Well-formed crystals may show sharp terminations and strong metallic reflectivity. Tarnish may produce subtle bronze or grey surface tones over time.

Historically referred to as “mispickle,” this mineral has long been recognised in British mining districts.

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Geological Setting – Brandy Gill, Eden, Cumbria

Brandy Gill is part of the mineral-rich regions of Cumbria, associated with hydrothermal vein systems emplaced within the northern Pennine and Lake District geological provinces. These mineral veins formed when metal-bearing fluids migrated through fractures in host rocks during late-stage tectonic activity.

As temperatures and pressures changed, iron, arsenic and sulfur combined to precipitate arsenopyrite within open cavities and fissures. The mineral is commonly associated with:

• Quartz

• Galena

• Sphalerite

• Pyrite

• Chalcopyrite

The mineralisation in this region is linked to complex structural geology and long periods of hydrothermal activity. Arsenopyrite often occurs in metalliferous veins that were historically worked for lead, zinc and other metals.

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Crystal Characteristics & Notable Features

This specimen may display:

• Bright metallic prismatic crystals

• Distinct crystal striations

• Sharp monoclinic crystal habit

• Natural quartz or host rock matrix

Arsenopyrite crystals frequently exhibit longitudinal striations due to growth patterns during formation. The metallic lustre and pale silver-grey colour are characteristic features of the species.

Due to its iron content, minor surface oxidation may be present in some specimens, contributing natural tonal variation without affecting structural integrity.

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Collectibility & Historic Mining Significance

Arsenopyrite from named British localities such as Brandy Gill is highly valued among collectors of UK sulfide minerals. The mineral holds importance both scientifically and historically, as it is a key ore of arsenic and often associated with precious metal mineralisation in some deposits.

Collectors appreciate Cumbrian arsenopyrite for:

• Recognised historic locality

• Classic metallic crystal form

• Association with traditional British mining districts

• Strong display aesthetics

Specimens from Eden and surrounding districts represent a tangible connection to Britain’s long mining heritage.

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Authenticity & Presentation

This Mispickle (Arsenopyrite) crystal has been carefully chosen to highlight the natural crystal form and geological character of Brandy Gill material. The image shown is of the exact specimen you will receive.

Included with your purchase is a Certificate of Authenticity lifetime guarantee generic card confirming this is a genuine Arsenopyrite specimen from Brandy Gill, Eden, Cumbria, UK.

A classic example of British hydrothermal sulfide mineralisation, this specimen combines geological significance, metallic crystal structure and historic provenance in one authentic collector piece.