810 THE TROPICAL AGRICULTURIST [June 1, 190L 
The occurrence of corundum in the form of ruby is 
extren)ely rare in compEirison with the immense areas 
ia diffi-rett prrt" of the world where the opaque 
ooftisb ^aiiety is pleatifully distributed. Thsre «.re 
threa priiioiiial sduves wheuoe the rubies of com- 
merce are de ivea, viz ;--Biu-!,nab, Siam, an l Cf>yloti ; 
bnt t'lDy pre al^o found in uuimpoitaut qua;''Uti9si 
ia Brazil, Thib-.l;, Afghaiiistu,n, New Suatli Wales, 
aad the United States of America. 
The centre of the ruby-mining industry of 3urmj.h 
is the town of M iRct, and the ope.tationR of mining 
extend over an arer^ of upwairds of 400 square miles 
to the eastern baijk of the Irrivfaddy River. The 
rubies are found associated with garnet, graphite, 
and spinel in beds of course gravel, and embedded in 
more or loss crystalline limestone which exiata alter- 
nating with gn'^sitsic and schistoee rocks. By the 
ever abrading effects of the elements these igneous 
I'ocks have become disintegrated, the debris form- 
ing the gravel beds lying in the valley below. It is 
in these gravels that the finest rubies are found, the 
explanation of which probably lies in the fact that 
flawed a,nd imperfect stones are unable to withstand the 
hard wear and tear to which they are subjected by 
nature. They gradually get chipped aud broken up 
by the constant process of crrinding and pulverising 
which they are destined to undergo, leaving only the 
flawless and more perfect stones to suryive. 
In Siam, the most productive district of rubies is 
the province of Ghantaboon, Bo Wen and Taphad 
Hin being the principal centres of mining operations. 
Another locality which produces large quantities of 
rubies is Krat, in which province the most important 
mines are situated at Bo Van and Navong. In the 
district surrounding Ratnapura, which town is often 
alluded to as the " City of Gems," and Rakwana, are 
found the finest rubies in Ceylon. They are found 
in the detrital deposits of valleys, river beds, and 
mountain torrents, generally as water-worn pebbles 
and broken fragments. They are always associated 
with the paler and many-coloured varieties of corun- 
dum, which will claim our attention in due course. 
The colour of the ruby varies very greatly, for, al- 
though it is characteristically red, there are innu- 
merable diiJerent shades and degrees of depth of 
colour in which it occurs. The tone of colour which 
is the most rare, and which is, consequently, the 
most sought after by connoisseurs in precious stones, 
is termed "the pigeon blood " ruby from its resem- 
blance to the scarlet blood of a recently-killed 
pigeon. 
The rubies which come from Burmah more nearly 
approach to this desired colour than those from any 
other country and, consequently, they are propor- 
tionately of greater value, for it is only in rare and 
isolated cases that a gem of ■ the true colour is 
brought to light. Siamese rubies are generally much 
darker than the Burmese stones, and hiive a tend- 
ency towards being purplish aud puce in appear- 
ance. Although very occassionally a Siamese stone 
ia found the colour of which may be compared with 
the rubies of Burmah, th« majority of rubies from 
Siam are unsatisfactory from a marketable point of 
view. 
Ceylon rubies are different altogether from the 
rubies of either Burmah or Siam. They are very 
limpid in brilliancy and pale in colour, possessing 
all the qualities of the most beautiful and attractive 
gems, yet they do not rank among rubies of fine 
quality. The actual cause of the flfune-red colouring 
of the ruby has been the object of a great deal of 
most interf-Dting investigation by some of the greatest 
scientists of the day. Although it is believed that 
the many varieties of corundum derive their colour 
fiom the presence of most minute quantities of dif- 
ferent metallic salts, it has comparatively recently 
been discovered that th^: real came c £ the colour of 
tbe ruby is still unknown. The absence of any salt 
of chromium, wiioh was formerly inspected of caus- 
ing the red hue in ruby, has been conclusively 
proved by the most careful chemical analysis, and 
endorsed by the still more delicate method of epec- 
trum analysis. When oxide of aluminium is inaerterl 
into a partially exhausted glass bulb, and exposed 
to the aotioa of a hiah tension electric current, it 
flashes with £. Ijvely crimson giow, and it his bien 
di^nionstratcd, u .der similar conditions, that rubj 
itself will give pcec-sely tho same result. Moreover, 
if t.i the oxide of aluci'iiiuin be added some oxide 
of chromium, the glow will not be produced. 
If the light natu'ally transmitted (through absorp- 
tion) by th3 ruby be examined by the spectrosoope, 
it gives the same bands which are characteristic of 
tlie phonporesoent glow which comes from the oxide 
of aluminium, in the vacuum tube. Another curious 
fact is that white oxide of aluminium, when exposed 
to eleotric.i.l bombardment for a long time, gradually 
alters to a pinkiah hue. 
Altogether, it ie q .iite obvious thit some myiterioui 
property exists in connection with oxide of aluminium 
whic:h the science of ttie day has not natiefaolorily ex- 
plained. That the ruby has always taken the first 
place among precious stones is evinced by many 
references to this beautiful gem by writers of all 
ages, although, befora the development of the science 
of mineralogy, great confusion seems to have existed 
with regard to rubies as with many other precious 
stones. It is apparent that almost any red stone 
was classed by the Greek and other ancient races 
under the general headii g of •' carbuuculua," which 
doubtless included, besides the true ruby or red corun- 
dum, spinels and all the many different kinds of 
garnets. 
Pliny, for instance, although he gives the first rank 
to the " Carbuncle Amethyatiaontes " (our modern 
almandine garnets) describes under this heading many 
of the ch ef characteristics of the true ruby of to-day. 
The " Pantarbes " of Philostratus was undoubtedly the 
uiodern ruby, and the gem alluded to by Theophratus, 
as "Anthrax," was also probably ruby, for he writei 
of its value being equal to forty gold staters, about forty 
guineas, for a small stone, whereas giuiets were so 
common that theii value could not have been very 
gr'jat at the highly civilised period of which he 
wrote. Hoth the words '' Caibuuculus" and " Anthrax" 
were used in allusion to the 'burning coal ' effect of 
the stones described. The quotation, ' For wisdom 
is better than rubies," one of the many references in 
the Holy Scripture to this precious stone, proves 
that rubies were of considerable importance at the 
time of King Solomon, to whom the words are attrib- 
uted. 
From old v;ritings we learn that by the ancients 
the ruby was always enveloped in mystery and accred- 
ited with all kinds of stran,,'e properties and powers 
one of the most striking of which was the belief that' 
the stone possessed the power of shining of its own 
accord in the dark, emitting flashes of light dazzling 
to behold. It was also supposed to attract other 
gems in much the same way as a magnet attracts bits 
of steel. If a ruby were tied to the end of a string 
and lowered into a river, the bed of which contained 
precious stones, it would be found upon its w.thdrawal 
that the ruby would be encrusted with other gems 
which had been attracted to it — a most useful virtue 
indeed ! 
Ruby was used as a talisman against all kinds of ills 
bnt chiefly against fire, which virtue is illustrated 
in the legend of Chariolea, who, when condemned by 
the jeal'jus Arsace (.Slthiop VIII. 2), escaped un- 
hurt from the pyre by means of an amulet in the form 
of the espousal ring of King Hydispes, " which was 
set with the stone called Pantarbes, engraved with 
certain sacred letters embodyins;, as it has proved, 
some divine charms by means of which a virtue ia 
imparted to the gem antagonistic to fire, and thus 
giving to the wearei; immunity from hurt in the very 
midst of flames." A peculiar idea, not altogether 
restricted to by-gone civilisations, is that the different 
corundum gems alter or ripen in the earth, and that 
a ruby has changed gradually from yellow to blue, 
from blue to purple, and from purple to red, which 
