sdbuienes 
fe into reddifh-white, and from cherry and crimfon-red 
into blueifh-red and purple. The two laft of thefe varieties 
were formerly called almandine, a name now given by Karften 
‘The cryftal 
Fora fuller account, fee oon 
It is found i n Ceylon and Pees, in the fand of rivers, 
ac companied an zircon, hyacinth, &c. Though it is 
inferior in lultre and richnefs of colour to the oriental ruby, 
or red fapphire, yet when of a certain fize, it is much poe ai 
sagem. We are told that when the weight of a fpin 
ease four sein (fixteen grains) it is valued at half ae 
price of a diam of .the i weight. Mr. Brard has 
feen one at Paris sof 21 
It is extremely difficult, 0 or, aliens impoffible, to fettle 
connoiffewrs 
h 
pyrope and noble garnet (Barbary ruby ; r 
the Italians); and ie red topaze, which has hein the 
name of Brazilian ruby, and is frequently called ballas ruby. 
Ignorance has alfo given the name of ruby to red fluor {par, 
and to red quartz ; and it is probable:that to the latter are 
to be referred the twelve pale rubies seid in Volkman’s 
Journey through Italy, as having bee ented to the city 
of Venic he emperor John Ca ey a in 1343, and 
each of which is faid to be 2 the we ven ounces. 
e 
84.4. The oe es form 
tufually occurs is the four-fided pr ifm, fhorte 
anes 3 or ,in_ confequ 
folid ante of the bafe of a canine octahedror, on the 
lateral edges. (See ec as n commerce it is iad 
feen in irregular ly rounded piec 
The pal colour of ae 
ul 
ety the wolcanic hyacinth is the 
Molt of thefe fubftances are generally fuperior in brillianc 
and value to the real hyacinth, which is 
as it feldom occurs of a moderate fize without being im- 
aulty. 
e name of jargon, a corruption of zircon, is generally 
given to thofe varieties of hyacinth which are nearly ete 
lefs, greenith, ee and alfa brownifh-red. 
firft of thefe mo eemed $ — art acca them 
by expofing light-c meds arieties to of fire 
which renders them toate In this pan ae: fe 
duced by art or nature) they are improperly called diamans 
bruts by French jewellers, a often fold for real diamonds 
of inferior quality. But as very {mall brilliants, it is often 
Sar 
fraight foliat 
of The 
the lefs efteemed, . 
pees mth a are principally ufed as an 
Ornament in mo 
The hyaci tg fe reo are brought from Ceylon, and 
other parts of India. acinths in {mall cryftals and 
a to be o alfo ae nd in 
Born jae its hardnefs ‘compared with that of 
tne denioad: to be as feven to one. Its fpecifie gravity 
is 3.5. 
It occurs colourlefs, like pure rock eryftal, yellow, red, 
and Amo ee the co olourlefs otal - Siherian 
appears on be the ae it is alfo fo very fine 
luftre in the Braz Hey in New Holland, where it has been 
lately difecvercd o occurring ae as rolled piec 
The yellow is the ufualand chara¢teriftic colour of this ftone ; 
it occurs as pale wine and ftraw colour in the Saxon topazes; 
it is fometimes fo very ert that the seas appear < almoft 
colourlefs. 
They, xO 
that of vba which is common rock “erly heated and 
aed red by the sblrption of a red folut 
ite Brazilian t s have often a *engs of blue, 
manner as the 
fometimes called Saxon or occidental chry/folite. 
then feen of a pale lilac blue, but frequently what is exhi- 
bited as topaze of this colour, turns out to be nothing but a 
very pure variety of amethyft-quartz. 
The crofs els of all varieties of topazes is perfetly 
po iny ftalline ead more frequently oc- 
curring among the topazes of commerce, are four, eight, and 
fix-fided oblique nn generally on longitudinal itreaks, 
and efpecially in the Brazilian, (egies & alow four- 
fided pyramid, h is now and then ges truncated. 
The white Siberian topaze is often found in very large 
cryftals, which yi pean in general tafe p pure than the 
middle-fized and {mall ones: when heated. they give = 
; eleétricity. 
eated, exhibits pofitive, the other negative eGhrictye 
Saxon topaze, which is moftly feen in cryftals broken on one 
extremity, or {till attached to its matrix, which is generally a 
k, become 
Thet 
yoya Be» 
