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Lazurite
1. Lazurite belongs to felspathoides group.
Chemical composition—3(NaAlSiO4).Na2S
Crystallises in cubic system.
Hardness—5.5
Specific Gravity—2.38-2.45
Lustre—vitreous
Fracture—uneven
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5. Commercially also known as “Lapis Lazuli”.
Actually, Lazurite is a mineral. Lapis-Lazuli is a
rock which is rich in Lazurite.
It is an idiochromatic mineral characterised by
strikingly rich “ultramarine” blue colour.
6. Colour is also referred as “Berlin Blue” or “Azure
Blue”.
Lazurite originates from thermal metamorphism of
sulphur rich impure limestone.
It is invariably associated with crystals of pyrite
and veins of calcite.
There is a belief that Lazurite protects the weaver
from evil.
7. There are many substitutes marked as Lazurite or
Lapis. Like dyed marble or limestone.
Jasper stained blue is called “Swiss Lapis” or
“Swiss Lazurite”.
In the stained substitutes, pyrite inclusions are
typically absent.
Lazurite is one of the earliest known gems, held in
eastern by Harappans in west India.
8. Although Lazurite is known from different
countries, like Siberia, Russia, Chile and USA, the
Afghan Lazurites continue to be esteemed.
The most important mine for Lazurite is in
Afghanisthan.
The colour of Afghan Lazurite is so intense and
pleasing that, its powder was used for painting in
ancient times.
9. Many beads of Lazurite were recovered from
Harappan sites. They were either imported or
mined locally.
There are few repoerts of Lazurite from India.
Rajasthan—Nagpahar hills of West Ajmer.
Madhya Pradesh—Bamasur hills of Bhandara
district.
Kashmir—Zaskar Hills.
