“to thofe that have prifmatic truncated pies and are lefs_ tion to reiufe aginowledgin it. n fuch a diftinGi 
hard and {plendid ; ee amon thefe he has "the emerald, rarer as it m jear, be confidered as eage ufe-. 
je {peaking, and into gems _ the fecond order. ‘To the former firft rate gem, often equal in ice - a diamond of the fam 
refers he ond. 
GEMS. 
cope was oe munea which, ae the refultson record, zilian ch 6. Saxon topaze and chryfolit ite. 7. The 
and fro e places where the fuppofed lapis ed was chryfolite eaete fpeaking (thefe are the apatite and afpa- 
found, we somleer ter - believe did (ees ha us {ton 
ne, or phofphate of lime). . The ieee (Zir- 
At the time when mineralogy emerged from the clout con, » Haiiy). To the gems of the fec 
in.which it had but too long been involved, the clafs of by him the garnet, tourmaline, and peta n (the 
gems, alfo diftinguifhed by the e appellations of precious, hard latter is a yellowifh-green var malin}, 
variety of tou 
fiones, pierres fines, nobles, precieufes, edel-fteine, attratted of rhomboidal {chorl Care bafaltic borablen)), oa 
:acourfe the principal notice of the fyftematic writers; they with what he calls fchorl argileux, and {chorl cruciforme 
were, as far as the fcientific knowledge of that period would oo or crofs.. ioe ne 
allow it, freed of extraneous fubftances; thefe fubftances either of the two prevalent fyftems of the prefent day 
were more ennaes examined, ‘and oe attempts made to confider the gems or precious itones — afeparate clafs ; that 
define and arrange them. Accor to Baumer’s defini- of Werner, hewevee *, not profeffin pay great attention 
tion, dan - - havtet heavieft, ts anfparet ftones 3_ to bine ir dechoea's conitituent parts, places almoft ll of 
and of peculiar luftre. of the writers of that pe eriod becaufe their more eens characters bopek them rather 
‘clafs them with the lapides vitrefeentes (to which moft of the of the filiceous than any other clafs of fofiils. ‘ 
foffils belonged that are now comprized by Werner under his fyftem they oc paeek Ta — of the firft clafs « fub- 
flint-genus ); zeus, Original in all his proceedings, ~ flances terreu san v1 i the diamond and. 
come the, falts < s ig the generators of seal con in- topaze, the former of “which is s lalfed with the ‘ fubftances. 
a a the different gems according to their form, as far combuttibles non a eect ues,’’ the latter,,under the appella- 
e was acquainted with it, among thofe falts of which tion of « filice fluatée shuminentes? with the * fubftances aci- 
hey refpe@ively appeared to exhibit the cryftallization. diferes.’’ 
‘Thus the diamond, becaufe, it cryftallizes in the manner of |= Though, owing to a great diffmilarity in their *char sere 
alum; is called by him alumen adamas ; after him Wallerius the ftones called pr ecioitsy OY gems, cannot, according to an 
applies the term of gemme pretigh fine to thofe precious found principles of claflification, be made to form a fub-di- 
ftones that — the cryfta um's"referring to vifionin a fyftem o ory Gtognot y a certain aflemblage 
them not only the diamond and i draphael but alfo the of ftones, poffeffed of a fuperior weight, luftre, and hardnefs 
fapphire and oriental amethyft whic : i ould certainly united to comparative fcarcity, remains ftill, by general con- 
never have feen in that formes and the aoe minus pretiofe {ent, in the pofleffion of that title, a se would be affecta- 
ftandard, and dividedhem into three clafles, viz. cae a seca of any aa anlnad n miner: a - ‘but this isno. 
; griental nl a pan a : feven Laan prifinatic reafon why we fhould neglect other points of view in which — 
““éolours for the genegg h clafs, while the different > thofe iy ee may be confidered. ‘Thus economical mine- 
fhades conftuted the es ‘This-thought Ww he ma con- ralogy may well be allowed to arrange its materials in a man- 
ceived, muft haye appeared a one; for except in the ner different from that which the f be ae writer would. 
diamond, it i&the colour he ed by the tuftee of the choofe to adopt; and an affemblage of min ubftancesy . 
m_ which. piincipally ftrikes the beholder; but having — particularly valued as articles.of. ornament el luxur > may 
fan his idea&ichiefly from ftones cut and polifhed, that with propriety be made to form a fubdivifion ia f {uch an ar: 
excellent man was not aware oat the fapphire alone exhibits rangement. But though fuperior hardnefs, lufire,.and value - 
almoft all the varieties of colour obferved in other gems. are jaid to conititute the eure Roni peice the fubftances.. 
The chevalier Baillou appears to have ah the ia a ete in queftion, it is no eafy m to draw the : line epi the 
ic i s juft mentioned roperti rties are "e fufficiently leffened ¢ 
on defer ne oe his the oath of sie inapplicz cable. We fhall in this aa le. 
hich, by unfortunately “for {cience, was never contider as gems or precious ftones all thofe apparently fili-- 
colour is one of the moit cafual ceous, blancs that, with more or lefs rae ogee ave - 
ay fe fubftances, and that much greater pe ‘yan quartz, and the ecific & avity of : 
tions: Jeveral machines of his own invénition, ss ower, aon, emerald and eryl, to 
) (anayt that of qua opal, though the ab+ 
introduces the gems ‘or precious ffones, as a eer oular ane of fence of two of the ae charters would exclude it from - 
rhineral fubftances. He divides them into gems firiftly this.aflemblage; yet it is.by co n confent pronounced a - 
me 
elafs he I. 2. The, oriental ruby; fize, and mutt therefore remain with the pr ecious ftones. . 
fapphire, a and to topaze (shih ene latter were firfi afcertained  Diamond.—Of tl lit 
by this celebrated cryftallographer to be one and the fame lydétailed account has. been given under that word, to ehh 
fubftance: differently coloured). 3. The fpinel... 4. The- we refer, but.add in this place fom eae more particus 
Brazifian ruby, fapphire and ae (which are all three eee conneéted with the fubject of ao art 
true topazes.) 5. geen. Stherian beryl, and Bra- It, ig well known that brown, owt bey and ane 
pot a 
= 
