Helgustadir mine
Helgustadir mine is a mine in the east of Iceland where Iceland spar was mined from the mid-17th century to the 20th century. It is the source of the largest and clearest known Iceland spar specimen and the source of most museum specimens of Iceland spar.
It was declared a nature reserve in 1975.
About
Location
The mine is located near Eskifjörður, east of Iceland. Helgustadir mine consists of two mines, known as the upper and lower mine.Uses
Crystals from this area are known for exceptional clarity, leading to the mineral being named "Iceland spar".Iceland spar from Helgustadir mine was used in optical devices used in physics, chemistry, and geology, most importantly Nicol prisms.