1. Amber
This is a fossilized form of resin consisting of a mixture of
hydrocarbons plus succinic acid. It was originally extruded from
the trunks of various types of tree, including the conifer, some
20 to 60 million years ago in the Miocene to Palaeocene
period.
The Greeks gave amber the name electrum (i.e. 'sun made').
Subsequently, amber was found to produce a negative
electrostatic charge when rubbed, and to be capable of picking
up small fragments of tissue (an ability shared by several of its
plastic imitations).
2. Because of its initial association with amber, this phenomenon gave rise
to the word 'electricity' which was coined from the Greek electrum.
Amber is usually a pale yellow-brown translucent to opaque material,
but
reddish-brown, greenish, bluish-grey and black varieties are also found.
Sea amber (also called 'sea stone' and 'strand amber') is recovered from
the Black Sea, the coastline of Sicily, and from the shores of the Baltic,
where it is known as the 'gold of the Baltic'.
Pit amber is mined principally in Palmnicken near Kaliningrad
(formerly Königsberg) in the USSR. Less important sources exist in
Mexico, Romania, Myanmar (Burma) and the Dominican Republic.
3. Pieces of amber that are large enough to be fashioned
into gems or ornaments are called block amber. Smaller
pieces of acceptable quality are heated to about 180°C
and compressed together (or extruded through sieves)
to form reconstructed or pressed amber (also known as
'ambroid').
The majority of amber from northern Europe has been
treated in this way so that it can be moulded easily into
beads of various shapes
4.
5.
6. Amber
Amber was one of the greatly appreciated gems in
European countries for several thousand years.
Not much importance was given to amber not only in
ancient times, but also in recent years.
For scientist, it is an amazing substance containing
ancient life preserved intact.
Several museums in Europe and America have
numerous objects preserved in amber.
7. By and large mineralogists do not pay much attention
to amber and some authors have not even included in
the text books of mineralogy.
Amber is a fossil resin discharged by ancient pine
trees and subsequently buried in sediments after
transport.
8. During the course of fossilisation over several million
years, resin undergoes some alterations.
Its hardness increases and it becomes less reactive to
organic solvents.
It is an amorphous substance consisting of
hydrocarbons.
Though the composition slightly varies from locality
to locality, by and large, it can be expressed as C10H16O
and hydrogen sulphide may be present.
9. Specific gravity= 1
Hardness=2.5-3
Refractive Index=1.54
Brittleness and sensitivity to breaks into fragments.
On prolonged exposure to dry heat it develops a
network of fractures on the surface.
It soft’s at 1800
c and melts between 2500
c and 3000
c
10. Colour=yellow, yellow-brown to reddish brown.
Bluish, greenish varieties are also there.
Transparency depends on amount of inclusions
present.
Lustre= Resinous
Fracture= conchoidal
Amber is found in sedimentary rocks and associated
coal and lignite.
11. In India, some disseminated ambers are found in the
tertiary lignite deposites in Panandro mines in kuch,
and Rajpardi mines in Rajpipla in Gujarat state.
They are not of block amber type, but are of small
dimension and devoid of organic remains.
Local people use of a “Loban”, a substance for
producing aromatic fumes and as insect repellent.
12. Amber is fossilized tree resin, which has been
appreciated for its color and natural beauty
since Neolithic times.
Much valued from antiquity to the present as
a gemstone, amber is made into a variety of
decorative objects.
Amber is used in jewellery. It has also been used as a
healing agent in folk medicine.
