, capital of the
department of Junin, 107 m. (221 m. by rail, via Oroya) N.E. of Lima.
Pop. (1907 est.) 10,000. It is situated on the plateau of Bombon, 14,280
ft. above sea-level, and in the midst of one of the oldest and richest
silver-mining districts of Peru. There were 342 silver mines in this
district in 1890, and at the end of the 19th century the average annual
output since the discovery of the mines in 1630 was estimated at
1,600,000 oz. A decline in the silver production having set in, the
American company which had become owners of three-fourths of the mining
properties in the district turned its attention to the extensive copper
deposits there, built a railway to Oroya 83 m. distant, another, 25 m.
long, to the coal-fields of Gollarisquisga, north of Pasco, and then
erected large smelting works (in which 2500 men were regularly employed
in 1907) 8 m. out of town and 4 m. from limestone beds. The railway to
Oroya was completed in 1903, the coal mine branch and smelter later on,
and in 1907 the copper output was 20,152,000 lb. The town of Pasco is
badly built and unattractive, and is inhabited chiefly by mining
labourers and their families. Its population is increased 50% in times
of great mining activity. The name Cerro de Pasco is that of a "knot" of
mountains uniting the two great ranges of the Andes at this point.

CERTALDO, a town of Tuscany, Italy, in the province of Florence, 35 m.
S.S.W. by rail and 18 m. direct from the town of Florence. Pop. (1901)
town, 4552; commune, 9120. It was the home of the family of Giovanni
Boccaccio, who died and was buried here in 1375. His house (of red
brick, like the other old houses of the town) was restored in 1823 and
fitted up with old furniture. A statue of him was erected in the
principal square in 1875. The Palazzo Pretorio, or Vicariale, the
residence of the Florentine governors, recently restored to its original
condition, has a picturesque facade and court adorned with coats of
arms, and in the interior are various frescoes dating from the 13th to
the 16th century. The town as a whole is picturesque, and lies on a hill
426 ft. above sea-level.

See R. Pantini, _S. Gimignano e Certaldo_ (Bergamo, 1904), p. 101 seq.

CERUSSITE, a mineral consisting of lead carbonate (PbCO3), and an
important ore of lead. The name (sometimes erroneously spelt cerusite)
is from the Lat. _cerussa_, "white lead." "Cerussa nativa" was mentioned
by K. Gesner in 1565, a