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Fact sheet


Sphalerite or blende is zinc sulphide and is the main ore of the metal zinc.

In Cornwall, sphalerite was found in many mines, often closely associated with lead-bearing minerals. The majority of Cornwall's zinc was recovered from mines whose main product was lead, helping to sustain them when the production of lead alone became unprofitable.

This specimen of massive, pale-coloured sphalerite came from Lambriggan, a small lead-zinc mine 4km east of St Agnes, which was worked in the mid-1840s and again in the late 1920s. The main early use of zinc was in combination with copper to make the alloy brass, but the corrosion-resistant coating of iron and later steel would soon become its most important application. By 1850 the British galvanising industry was using 10,000 tons of zinc a year for the protective coating of steel.

Chemical Formula: ZnS

Specimen no. TRURI: 801.1521
Location: Lambriggan
Grid Reference: SW 761 511

Mindat http://www.mindat.org/min-3727.html

Additional images
  • Sphalerite 7 cm across
  • Sphalerite 7 cm across
  • Sphalerite 3 cm across
  • Sphalerite (with yellow chalcopyrite) 3.5 cm across
  • Sphalerite 3.5 cm across
50.317214, -5.146459
About this collection

This Collection focuses on Cornwall and West Devon’s mineralogical and mining heritage.  The specimens it features are drawn from the collection of the Royal Institution of Cornwall (RIC) held at the Royal Cornwall Museum (RCM). 

This collaborative project involving the RCM, the Cornish Mining World Heritage Site and The Open University explores how access to the RIC’s mineral collection and the stories it can tell can be widened using digital technology.  It includes radioactive minerals from Cornwall that would otherwise be inaccessible to the public for health and safety reasons.

Sample details

Category guide  
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Accessory minerals
Minerals that occur in very low abundance in a rock. They are usually not visible with the naked eye and contribute perhapssver, they often dominate the rare elements such as platinum group metals.
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A term used to group together related samples that are not already gathered into a single Collection. For instance, there is a ‘SW England granites’ theme that includes such rock types as granite, hydrothermal breccia, skarn and vein samples.
A general term used to label a rock sample. It is a useful way of grouping similar samples throughout a collection. Category names are often, but not exclusively, common rock names (e.g. granite, basalt, dolerite, gabbro, greisen, skarn, gneiss, amphibolite, limestone, sandstone).
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We would like to thank the following for the use of this sample: