New-York tribune. [volume] (New York [N.Y.]) 1866-1924, 1897-05-16
THE HOME OF THE DIAMOND
PRODUCT OF THE KIMBERLEY MINES.
THE WONDERFUL ABUNDANCE OF JEWELS IN
VERY SMALL AREA.

VERY SMALL AREA.
The fact THAI the African diamond fields. at pres
ent the worlds chief Of supply OF the high-
est-prized Of gems have been discovered ana ue-
veoped entirely since Queen Victoria ascenoed .he
throne associates the diamond In a pecuhariy NJ
tins manner with Her Majesty's Diamond jubilee.
Before the Kimberley mines were discovered most
of tho diamonds added the worlds stock came
from either Hindostan or from Brazil The largest
deposits were found in Golconda. In the Hyderapao
territory, and IN Minas Geraes. IN Brazil Inc
African discoveries first showed sclenthlc men
what the origin and native place or the uiai'o'''
really was In the Indian and Brazilian fields 1t
was plainly not native to the soil, and was picked
I'D out of differing formations. In South Africa
il found in a rotten rock apparently lorihhs
part OF the earths crust and not mere superhciai
deposit as the others had been. The great mines IN
this region according to a correspondent OF Ihe
| London Standard" are situated within a circle
about three and one-half miles in diameter There
are five principal mines the largest being only
about forty-hve acres IN extent: they are the Ia
nous Kimberley. Bultfontein De Beers. Du Tots
! Pan and Wesselton mines. They are OF fabulous
| richness Here the town OF Kimberley has sprung
up, and mining for diamonds Is carrieo Oh oi'
| vast and systematic scale.
! The district is about four thousand feet apove
sea level and lies the northern edge or p'a'ea"
| which extends from the BokkeVeldt Mouh'aihS'
| near the Cape OF Good Hope. 20 tho border OF inc
| TranSVaal
| Free State two being Of considerable note, one
| thirty the other sixty miles away. with several
| more Of less importance both there and IN the
| Kimberley district. Tho river washings are SUI
| continued but tho yield of gems from thci ~ hot
very rich or steady. Mining In the rock was cai''cu
on at first in a rough and-ready tashioh, D"' 'i'
| that has been changed In most parts OF the as
trict after clearing away some feet or surface SOIL
| the excayator comes upon dark coaly shaie
| hundred feet or m ore thick. Beneath th.s lies
mass of igneous rock. allied to basalt, more than
three times as thick, and that is sucoeeoed by
blackish ehale, with bands OF hard sandstone. But
here and there instead of the shale. though sur
rounded by it. like 4 pond In a field. is u mass OF
curious rotten stuff In which sometimes fragments
of shale and sometimes hard mineral grains can be
seem
THE DIAMOND-BEARING ROCK
This at first is Of a rusty yellowish color. then
in about one hundred feet It turns to dull
green and becomes O little more solid-sometimes
distinctly harder than dry clay. The two rocks are
Identical in origin. but the upper. or yellow
ground" is more decomposed than the lower. or
blue ground Gradually the rock ceases to yield
to spade pick; 1t has to be Quarriod in the usual
way and is quite hard as a bit Of good lime
stone. 1t has quite different appearance
seeming consist largely Of fragments varying IN
from at least two inches in diameter down TO very
e ea re mnsTaS en brocn bit occasionally
looking like cry stals All these are set in a Dark
as or sc o 7o
I'll b hgge Pss or N
and underlying rocks: ard these go yercaiy domh OWL
not less than fifteen hundred feet. At hrst the ma,
terial was pegged OUT IN numpeI , o. sia
to work But by degrees many difficulties arose As
! the excavations were deepened, the CLAIMS were
terial We're constantly occurring not only. in the
! pipe itself but from the country rock at Its
pensive; cooperation and command Ct capital were
soon absolute necessities About 1850 the mines han
united under tho name Of the De Beers ConsoI,
a the contTy rock from Which levels are driven
| TO tho pipes" The diamond bearing rock Is quar-
up to the surface DurIpg his process amq Tpd
be egt mat nc mSrc where it is
exposed to atmospheric action, IN ordeE that. II
e rs be nvGded OF Splitting the Contained d
nonds by crushing it up This hGweyer rs some 70
various processes. including washing, the mineral
residue is picked over for diamones. All sorts Of
The quantity of diamonds which have been pro
indeed the directors find 1t needful TO limit the
hap By the the end Of 1852 about ten tons
had been Yielded by these mines valued az sixty
Ihs Hs English scientist s Ss5HGsG
stated in rsSen, Ss T on tn ard ax fe
high; the annual product is now about half ton,
and eight thousand persons, OF whom rather
moro than one-ffth are white, are employed IN inc
works. The above estimate includes diamonds 81 81
for H nosns but cuiing PURPOSES, While another
may be a gem OF the first water The south Al A.
brofen eolored specimens are not rare and
sgh yellow nge Is n fo ie me 81
eral mines that an expert can generally identlfy
the locality from which a stone has come: Large
/ specimens are not uncommon The biggest round
rather under two inches from point to point anu
| weighed nearly four ounces Troy.
UNSETTLED POINTS IN GEOLOGY.
What IL the real nature of this rock and how the
diamond has been produced. points not easily
determined. Biologists have not yet settled the
former point or whether the diamond grew
where It is now found The rock, we have said,
is full Of fragments. many Of them being minerals,
such Divine. garnet. MICA. an aueite' etc. &c
gether with serpentinous rocks and shale. The
and carbonate Of lime. The late Professor Caryill
sSr Of serpentine IKE that found parts
England He supposed that me ihclude ca Ira
1t forced its way upward IhH mp bd y
volcanic breccia produced by a series OF explosions
of gas and steam. and afterward modired by the
pipes are the threats OF volcanoes which only
discharge broken rock. steam ana water. AGAIN
d d where it is now found. Others believe IL
like the garnet. ausite etc to have been lofrneo
Lewis held that 1t formed by the action of the
molten magnetism: rock on the carbonaceous shalcs
Diamond undoubtedly 10 only one form o. pure car
bon Of which the homely but useful carbonate Is
another and the no less home nor les 6rd seR
Abundance Of Divine and other fcrro- me gne@ian
minerals may be sign!hcant, for diamonds have
! also been found in meteorites composed mainly OF
Divine and iron. Here. though the carbon cannot
have come from shalc, the association Is sug-
| Cestiye Tho making of the diamond IS a compare
lively recent triumph achieved by NJ Mossan; this
though 1t has not revealed the natural process q
some extent points in the same directon-viZ, the
cooperation Of heat pressure, and base Ike lion
or magnesa. BY using the temperature OF TIC
electric arc he fused together carbon fnd iron. and
cooled the mass as TO produce great pressure on
the Interior Tho carbon crystalli1ed ont In tiny
diamonds instead Of graphite According 10 FRO.
lessor Lewis the diamond was formed where II
now lies. Others, who think that his idea or Its
genesis may be correct. are of opinion. rs stated
above that the mandatory was deeper down In
the earth.