656 
A Defcripion of the Coafts of 
The Goad- 
nefs 4nd 
Value ef 
the Dia^ 
mtnds. 
The Rjuhy. 
Tbtif dif- 
ferent 
kjndff 
g9tdnefs 
(ffndvak^, 
ont any Multiplication. To try the 
goodnefs of a Diamond you muft cut one 
Diamond with another, and if the Powder 
thereof be of an Afh-colour, it is right, 
but if white, otherwifc^ for all other 
precious Stones except the Diamond 
afford a white Powder, and the more 
the Powder of the Diamond approaches 
to a Grey, the more precious it is. They 
have another way of trying the Dia- 
monds, by making them red hot, and 
afterwards quenching them in cold frcfh 
Water, and if they don't crack they are 
true and good. The true Value of the 
beft Diamonds ( provided they are clean 
and of a juft thicknefs) is computed thus : 
The juft Value of a good Diamond weigh- 
ing a Carat ( each whereof is equivalent 
to four Grains) is 80 dlders, or 32 Rix- 
doUars. Now to know the juft Value of 
one or two Carats^ you muft multiply two 
with two,thc Product whereof being four, 
this muft be multiplied with the value of a 
Diamond of one Carat^ wz. 80 CildtrSf 
the Prodnd whereof amounts to 320 Gil- 
ders ^ fo that according to this Compu- 
tation, a Diamond of 20 Carats is worth 
32000 Gilders^ and according to the fame 
proportion, one of 100 Carats no lefs 
than 800000 Gilders, 
The Ruby, call'd Rubinus or Carhmcw 
Im by the Latins^ Mamwikam by the 
Malayans^ Mattamora by the Siamefes, 
and Laal hj the Indvfihans ; it will en- 
dure the Fire for a confiderable time. 
There are three fevcral forts of Rubies, 
fome are of a high red and brillant colour ; 
thofe of a dark red colour, tho they 
carry a very fine Luftre, yet are not fo 
much valued as the formeto The Oriental 
Rubies are call'd Efpinelleh thofe of Gef" 
many are very hard, but inclining to a 
dark brown, and therefore of lefs Va- 
lue^ notwithftanding which they are 
true Rubies : they feldom exceed the big- 
nefs of a good Pea, and are very thin, 
and the Stone-Polifliers make them thin- 
ner, ftill to increafe their Luftre. The 
EfpineUes are of much brighter Colour, 
but not fo hard, and confequently of 
lefs or more Value in proportion to their 
Hardnefs, fome being as hard as a Sa- 
phir. 
The Carbuncles are adulterated with 
Sandaracba^ but thefe falfe Colours are 
foon difcovered in the Corners of the 
poliflied Stonesj which don't receive thefe 
Colours, The Oriental Carbuncles 
are likewife of two different kinds, fome 
are of a dark brown Colour, the others 
are bright and carry Luftre like Fire, and 
shefe are the moft precious. The Rubies 
are apprais'd like the Diamonds by Co- 
ratSy one, two, three, or more, with 
this difference, that the Rubies tho of the 
fame Weight, are fomewhat bigger in 
proportion than the Diamonds, and 
without the leaft Clouds or other De- 
fers. 
ThQ Smaradg or Emerault^ called T4- 75^ Erne- 
marulhy thQ ySrabians, and Jafche by the wult. 
Indians, is one of the precious Stones cal- 
led Z/^apayt/^os by the Creeks^ and Efma- 
raude by the French. They are of three Of three 
different kinds. Scythta and Egypt pro- ki^^^ 
duce thefe Stones, as well as the Eajt-ln- 
dies. They endeavour to imitate them at 
Paliacatta and Bifnagar in Glafs. Thofe 
of Scythia are accounted the beft, thofe 
of Pfj'Marethe next in Goodnefs, of a 
dank green Colour, very hard, and more 
tranfparent than thofe of xht Ea^- Indies, 
Thefe laft are harder than thofe of Peru^ 
but much lefs regarded. Thofe of Peru 
are of a pale Colour and brttle. The 
general Opinion is, that in cafe an Erae- 
rault fhould be found excellent in all its 
Parts, nsix,. in Colour, Shape and Tranf- 
parency, it would be comparable to a 
Diamond of the fame bignefs, nay Their 
would even furpafs it in value, by reafon "^/Hf, 
of its rarity^ 
The Saphir is called Mtla by the Arahi- Tht$v^\at 
anSy and Milam by the Malayans, They 
are of two forts, thofe of a dark blue Co- 
lour are the beft, thofe of a pale Colour 
refembling the Diamonds, the worft. 
They are found in Malabar, Calecut, Ca- 
nanor^ in the Kingdom of Bifnagar, in 
thelfle of Ceylon, but Siam and Pegu pro- 
duce the beft. 
The Hyacinth called 'Yaitiv^®^ by the ne Hya- 
Greeks^ is a red Stone, not unlike the cioth. 
Carbuncle, but does not endure the Fire, 
it is fonnd in Spain the Jewellers fell 
fometimes the Stone called Ethtopis, for a 
Hyacinth : they are of two kinds, one 
red, the other inclining to a yellow. 
The Jmethifi, called 'A/^e3u?^ by the The Arae= 
Greeks, is of a purple Colour ; thofe that *ift 
are found in the Eajl- Indies are preferr'd 
before the reft. 
The Jafptr fo called by the Latins, and ibejitpk 
'Ixaui^ by the Greeks, is of two different ^iwrf fn 
kinds, fome being of a lovely green Co- ^^mw* 
lour, like the Enter aults, and of fuch a 
bignefs, as to ferve for Materials for 
Drinking-cups ^ fome have the green 
mix'd with white ; fome are of purple, 
others of drofe Colour with variety of 
Flowers in them others are dark brown 
and blew, with white Veins fome are 
Marble on one, and Jafper on the other 
fide. 
The 
