44 Thoughts on Gems , 
their being void of any faline Taffce, and 
their Indilfolubility, fufficient Objections 
againft Salts being the Bails of Diamonds, 
Rubies, Emeralds, Granates, &c. fmce it 
is obfervable, that Glafs, in whofe Compo- 
fition Salt is a principal Ingredient, proves 
alfo undiffolvable, is endued with a con- 
fiderable Degree of Hardnefs, and (as its 
component Salts cannot aCtunlefs diifolved) 
is confequently inilpid, or rather abfolutely 
taftelefs. 
Whoever iliall pleafe to repeat thefe Ex¬ 
periments after me, will I believe be fa- 
lisfied, that the Cryitals {hooting from a 
Solution of diitilled Verdigreafe, which 
is a Vitriol loaded with Copper; thofe Crys¬ 
tals I mean whofe Roots are at the Ex¬ 
tremity of the Drop, and their Points in the 
ambient Fluid, refemble nearly the fhoot- 
ings of Emeralds both in Figure and Co¬ 
lour : that the Cryflals of Ens Veneris , a 
Preparation of Iron, wonderfully emulate 
the Topaz, &c. 
When the faline Particles combine, without any metal¬ 
line Admixture, the Concrete appears colourlefs, and 
probably forms pure Cryftals or Diamonds. The extreme 
Hardnefs and Luftre of the Diamond refult perhaps from 
the almoft abfolute Homogeneity and Purity of its component 
Particles, whofe Sides or Planes having admitted no foreign 
Particles between them, touch in many Points, and be¬ 
come thereby almoft infeparable. Saline Particles in fuch 
Purity meet, however, but very feldom, and in fmall Quan¬ 
tity : but as mineral Salts abound almoft every where, and 
efpecially about Rocks and Mines, they frequently appear 
in Shoots or MafTes, blended more or lefs with talcky or other 
Matter, and probably conftitute our Cryftals, Spars, 
