286 
METALS. 87. Pltimbum. 
rorneum. White, without metallic luftre, eafily melting before thff 
blowpipe,, and in a greater heat entirely evaporating' 
Spielman Jour^. d( phyf, 1774- Dec, p. 455. 
Freber n. afl. petrap 3. p. 269. 
Found in the mines of Lotharingia and Bohemia. 
Plumbago. With metallic luflre, cafily melting with fulphurous va- 
pour and flame, and leaving a bead of lead without 
any mixture of filvcr. 
Plumb, fulpluire mi neralif. C.ronfl 1S5. 
Plumbum fulpliure, &c. Wall. fyA. 2. p. 305. n. 5. 
Compaft galena. Kirovan miner. 2. p, 218. 
Contpift galena. Thomjon chem. 4. p. 70 
Found in the lead mines of England and Scotland, Norovap 
Soveden, Spain^ Saxony, &c, in mafs, nodular or fpecular- 
colour lead-grey, and has a brighter llreak : texture compaftf 
and generally breaks into indeterminate fragments: fpecific 
gravity 7,444. it contains merely lead combined with ful- 
phur. 
galena. Of the colour and Jullre of lead, ponderous, foft, prefent- 
ing granular concretions, breaking into cubical frag- 
ments, melting with fulphurous flame and vapours, 
and wlien the lead is reduced to a glalfy oxyde leaving 
a bead of fil ver. 
Plumbum partic. cubic. Sy/t. nat. xii. 3. p, 133. n.^. 
Plumbum Jrgento mixt. Wall. fyfi. z. p. 302. n. 2. 
Common galena. Kirovan mineral, z. p. 216. 
Galena. Schme/ffer miner, z. p. \j%. 
Lead glance. Berhenh. outl. p. zbz. 
Sv^lphuret of lead. Fhomfon chem. 4. p. pi. 
Suluhure of lead. Sooverby Brit miner, t. z.^, 
Z. Compact, foliated or fibrous, between indigo-blue and lead- 
grey, fometimes ftriate longitudinally. 
Plumbum oompaftum. Sy/t. nat. xii. 3. p. 133. 
Blue lead ore. Thomfon chem. 4. p 72. 
Found in various parts of Great ■ Britain and the continent, parti- 
cularly Siberia, roalTu’e, in nodules, invefting, or fpecular,. 
and often coated with gold or filver mica : the cryitals are 
ul'ually cubes, double 4-fided pyramids, 4 and 6- Tided prifms* 
or varioully modified: texture foliated, with cubical frag- 
ments; it is brittle, fometimes loft enough to he cut with 3 
knife, and often ftains the fingers ; before the blowpipe it 
decrepitates, melts cafily with a fulphurous fmell, and if al* 
Ecrnately healed and cooled w’ill at laft vanifh leaving its filvei 
behind : it is compofed of various modifications of lead, ful- 
phur, and filver: fpccific gravity from 7,220. to 7,587. 
