There is practically no other hard semiprecious stone with
such a long and glorious story like jasper. For nearly three centuries
jasper has surely won its first prize in the Russian stonecutting art,
successfully competing with any other hard stones. "...On its treatment
our stonecutting industry was born and grown up, the Russian jasper
occupied the first place in the whole world for the richness and size
of its deposits, for wonderfully big articles out of it and for the
endless diversity of its tones," academician A.E. Fersman said 50 years
ago. The Urals has preserved its priority in the quantity and diversity
of jasper up to our times.
What is jasper? A jeweler or
a stonecutting master calls jasper any solid siliceous rock which give a
nice luster after polishing. A mineralogist though calls jasper only solid
rocks, consisting of tiny quartz grains, soldered by clay or siliceous
cement or chalcedony. Since the XVIII - XIX centuries geologists wanted
to know the mystery of the origine of this fascinating semiprecious stone.
And up to this date specialists continue to dispute about jasper's origine.
Some time ago academician A.E. Fersman drew a vivid picture of jasper
formation. "Several hundred millions years ago, in the so - called devone
period there was no modern Ural mountain - ridge. Sometimes shallow,
sometimes deeper sea with separate islands used to cover the place where
mountainous chains of the Southern Urals now are. There were no traces
of rockforming activity so far, but lava was already pouring out under
water, changing the usual landscape of the devone sea. On the sea - bottom
covered with pouring out lava there lived fauna various sea - animals with
siliceous skeletons. In the complicated chemical process their remains
piled up on the bottom, thus forming whole layers of siliceous silt -
A lot of millions of years passed,
and powerful processes of rockforming gave birth to the Ural mountain
range of 1200 km long. The jasper belt can be compared with a necklace,
as jasper deposits stretch themselves not like a whole stripe but with
separate jasper regions. Nowadays geologists count up to 207 jasper
deposits in 12 regions. What is jasper valued for? Jasper is a highly
hard stone: it can't be scratched with even the best steel instrument,
it is hard in treatment, but once it is polished, it preserves its mirror
luster for a long time.
The colours of jasper are long
lasting too. Jasper doesn't lose its colour like some presious stone do.
The main thing jasper is valued for is its colour, which is always different.
One is fascinated by fantastic mixture of colours forming most various
pictures. Sometimes the mixture of colour is so fine and complicated that
one can see a fantastic landscape on the polished piece of stone.