58 DEPOSITS OF PHOSPHATE OF LIME. [bull. 46. 
until 1800, and from that time until 1875 the mines had exported only 
124,156 loos of phosphorite. 
The Logrosan deposits were the first phosphorites found in Spain. 
The earliest mention of them is by William Bowles in 1782. 1 He says 
that at the base of the Guadalupe Mountains, and near the town called 
Logrosan, the royal road is traversed by a vein of phosphoric stone, 
running in a north and south direction. It was also mentioned by La 
Play, Proust, and others in the early part of this century. But the 
deposit did not attract much attention until Professor Daubeny, of Ox- 
ford, and Captain Widdrington 2 visited the Logrosan country in 1844 
and made a thorough study of the one vein then known. Later, in 
1849, Mr. Naranjo y Garza, by order of the Spanish government, made 
a survey of the basin of the Guadiana and gave a description of the 
Logrosan phosphate deposits. 3 
The Caeeres deposits were discovered in 1860 by Mr. E. De Luna. 
Ever since about 1855 the Spanish phosphorites have been worked 
at intervals. The phosphorite is of excellent quality, commands a 
high price, and makes as good a superphosphate as any phosphate 
known. But the expenses of transportation and the occasionally un- 
settled political condition of the country have been great detriments to 
the development of the mines. 
Analyses of phosphorites of Spain. 
[I. Logrosan phosphate, hy De Luna.] 
Water 0.40 
Boue phosphate of lime 82. 10 
Phosphate of iron 5.20 
Phosphate of magnesia 0. 30 
Fluoride of lime 7.31 
Carbonate of lime 1. 74 
Chloride of lime 0.40 
Silica 2. 55 
100. 00 
[II. Logrosan phosphorite, by Professor Daubeny.] 
Silica 1.70 
Protoxide of iron 3. 15 
Fluoride of lime 14.00 
Phosphate of lime 81. 15 
fill. Logrosan phosphate, by Messrs. Pelletier and Donadei.] 
Phosphoric acid 40. 12 
Silica and clay 3. 10 
Hydrochloric acid 0. 0G 
Hydrofluoric acid 2.27 
Lime 53. 50 
Peroxide of iron 0. (51 
Loss 0.79 
1 Natural History and Physical Geography of Spain, Madrid, 1782. 
"Quart. Jour. Geol. Soc. London, vol. 1, 1845, pp. 52-55. 
3 La Gazette de Madrid, July 22, 1849. Revista Minerva (March and July, 1855). 
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