The sun. [volume] (New York [N.Y.]) 1833-1916, 1894-10-07
MYSTERIES OF THE RUBY.
Extraordinary Pecuiiarities Presentss II
Its Structure.
Hom the Mineral Collector.

fFOHt the htneTuf tOuSTOr
In an address before the Royal Institution In
London Prof. Judd said that all the romance as
ISOLATED with famous jewels and their history IL
OF Insignificant interest compared with tho
fascinating actualities which science has dis
covered In regard TO the wonderful gem family
the aristocrats Of the mineral kingdom. Eight
years ago England was excited over the annera-
ton Of Burmah, and there were great expecta-
lions Of what was to happen when the British
capitalist got his hands on the celebrated ruby
mines Of that kingdom. Somehow or other these
expectations have not been gratifed
The rubies are not forthcoming. but II Ia not
to he presumed from this that Burmah has en-
joyed a false reputation for those remarkable
stones Of price. Prof. Judd showed that while
the ruby and its near relations are found In
many parts of the globe, II is in Burmah alone
that the gem is unearthed in it's purest and most
fiery form. The intense " pigeons blood color
and peculiar fire" of the Burmese ruby give
II extraordinary value, as compared with other
red stones which come into rivalry with u, for
under the name of rubies" great variety of
gems not truly entitled to the name have In
ancient and modern times passed muster.
The only substance which can truly be called
ruby" is pure. limpid, fiery red corundum. This
mineral. corundum, is crystallized oxide of
aluminium, and forms the basis OF nearly every
gem except, OF course. the diamond) which We
value for hardness, brilliancy. and color. A
crystal OF pure red corundum we call ruby"
crystal OF the blue variety is priced as " sap
phire," green crystal know as an
" emerald" and other tints known as aqua
marine, topaz and so on. Corundum is found
very widely distributed In the East especially
in Ceylon. Thibet, and Afghanistan, and in the
United States big masses OF impure blood red
corundum are found. from which isolated crys-
la -, a. sGaI.
claim the ruby a, a native nroduc, There are
a great many rod rival. m the BURMESE r,,ny
sn, ,,,h ,h. s 70 s"s n s,. ruoy,
Is so hard. They include the red spinel. the
ro.e tnpaz rod zIrcon rrbaIIita IN ,orr, a, ,our-
maine more priced in China than the ruby. and
the various garnets. This quality OF hardness Is
one y, ,hs mos, ys,u.h,a ,ss,nr.. In ,ha .,,hn
one Oh inc most sHiuAole features IN inc ruby
nor u enables the gem 10 @ke a hieh polish
The diamond is OF course harder and it is inter
eo'ns " ho'o Una. oho V, 'he hrs' producc'
evolved from the electrical iurnace-a crystal
lied compound OF carbon and silicon-is only
less hard , than the diamond itself
flows from the extraordinary peculi-
arities OF structure that Il nresents ss well a.
from the mysterious qualities that determine Its
striking color. II Is found in crystals OF great
variety NJ sban.s but all having n tendency N
5000 ~ 'ap.' ' "' ""''"t 'ohue"0J :"
the peculiar habit OF growth known to crystal
lOgraphers as "twinninR." Nv testing CRYSTALS |
OF corundum with polarized light its structurs
is found TO be wonderfully complex and under
the microscope its exterior face Is covered with
a strange network OF sculpture Indicative OF
changes
but probably the most interesting thing about |
the corundum CRYSTAL is the fact that II is nearly
always found 10 have enclosed and surrounded |
some foreign body or other which lies i'm |
prisoned in IT, Stranger still is The fact that |
these Included foreign bodies lie generally dis
posed OF in pianes meeting each o,bep AZ an
angie OF sixty degrees the result being 10 pro-
i uce the phenomenon OF asterism which Is the |
term given 10 the white star OF light which Is |
Observable on certain Jewels cut with a rounded |
surface. Very frequently the imprisOned pody |
is a minute bubble ~ gas or drop III liauid CON
tanning sometimes little CRYSTALS OF its own
The microscopic cavities containing these
things are often very numerous For "A long time |
the nature Of the gas and fluid Nd |
I'M the cavities remained a mystorv The Eng
fish philosopher Brewster was Induced to in |
vestigate the subject by hearing that a ruby /
" Inch an Edinburgh jeweler had placed In his |
mouth had exploded while In that nosition with /
unpleasant results Other inyestivators foi, |
Owed and Il has now been made certain that
The fluid is no other than LIQUID cArLonic acid |
gas reduced 10 that condition by being under
great pressure
The color OF the ruby Is another Of its
N ysteries. and one which Prof. Judd was