[ 93 ] 



nothing but Hardnefs to make it a per- 

 fed Imitation of the Diamond, Jo beau- 

 tiful is its Luftre. 



'Topaz, This is the Chrysolite of the 

 Ancients ^ it is always of a pure yellow, 

 or fineft Gold Colour, but of different 

 Shades or Degrees, from the deepeft 

 Saffron down to the paleft Amber, or 

 Straw Colour. Lead is fuppofed to in- 

 fluence it in this refpedl. The moft va- 

 luable is equal in Hardnefs to the Ruby 

 or Sapphire : They are feldom found very 

 large ; but the Great Mogul has one that 

 weighs near i6o Carats, which is of very 

 great Value. The true Topaz is always 

 met with in a Pebble-like Form ; it has, 

 when polifhcd, a glorious yellow Colour, 

 Cryftal, tinged with yellow, is often fub- 

 ftituted inftead of it by the modern Jew- 

 ellers, but the "Wheel difcovers the Dif- 

 ference ; for the very word Topaz is 

 much harder than Cryftal. They are 

 found in the Eafx and Weft Indies,, and 

 fome times in Europe, 



Emerald 



