of the P y r i t e s. 47 



From the affinity in fundamental principles bq- 

 twzznpyrit* andiron ore or iron-Hone, we may well 

 fuppoie the former generally to lodge with the lat- 

 ter i as pyrites chiefly confifts of iron, being only a 

 ■ fulphurated iron ftone ; much as cinnabar'is a ful- 

 phurated quickfiiver, or antimony, a fulphurated 

 arlenical* femimetal. called regnlus : and indeed we 

 find in iron-flone fmall cubes of iron Pyrites, as in 

 that of Orbis in Bohemia, And here 'tis' pecu- 

 liarly to be remarked, that the pyrites includes a 

 craverfing white limeftone vein, which fupplies the 

 true feh-ages •, circumirances I have alfo obferved 

 of the pyrites in the {tone-coal of Peterwitz. We 

 alfo find therein a copper-pyrites, or rather a cop- 

 pery pyrites traverfing it in veins as appears alfo 

 from the fame fftttd of Orbis. This the iron- 

 fmelters find to their coil:, when not furfkiently 

 feparated from the iron-ilone ; the fulphur, tho* 

 entirely forced out, leaves behind it in the iron 

 an untoward quality : and by means of the cooper, 

 from which fulphur is with difficulty feparated! 

 adheres Hill more clofcly to the iron, and taints it 

 'as it does all metals in their degree of mallea- 

 bility and metalliciry) rendering it brittle and 

 fliort. A coppery iron, indeed, does, when cold, 

 manifcft a fufficient degree of totaghhefs ; but 

 when hot, it eafily fnaps, falls to pieced, and folders 

 not again, and is leaft of all fit for rriakirig fteef 

 That the pyrites lodges near that red fort or >on- 

 ltone, called glafs-head by miners, and by dnig- 

 gifts. blood-ftone, cannot well be doubted of, tho* 

 I never faw nor read of an inffanCe of that fort 



fiii. 



»f* Dr \ M ^ der , Jn - Atiaiyfw of Mitiftbj* ftfefts to alio* 



of no ari.nic in the regulus of antimony. Our author S 

 according to the common opinion, viz. that ,}, e Ie ,, uks J/!!* 

 timony is a mercury feed by arfenica j r * u ' a > Ul an. 



