Penrose. j PHOSPHATES OF BELGIUM. 103 
as shown in the section above. Immediately under the Tufean comes 
the Ciply Conglomerate. This is a denudation deposit, and is known 
as the Poudingue de Ciply, or Poudingue de la Malogne. 1 In some 
places it immediately overlies the White Chalk, as in the neighborhood 
of Ciply, and at others it is separated from it by a very variable thick- 
ness of Gray or Brown Chalk. The Conglomerate consists of a mass of 
phosphatic nodules, shell casts, and fossils, cemented by a calcareous 
matrix. Sometimes the bed is cemented into a solid mass, and again it 
is loose, and easily worked with pick and shovel. There are numer- 
ous shells and remains of gasteropods, lamellibranchs, brachiopods, sea- 
urchins, and sponges. There are, also, many teeth and vertebrate bones 
of fish and sharks, all much worn and rounded, showiug clearly that 
they have been changed from the bed in which they were originally de- 
posited. Belemnitella mucronata and Ostrea vesicularis are among the 
common forms found in the bed. 2 The nodules vary from a quarter of an 
inch to 5 inches in diameter, and are generally of a brown color. They 
contain a small quantity of phosphate of lime (25 to 50 per cent.) com- 
pared with that of American and English phosphates, which rarely run 
under 55 per cent, and 50 per cent, of phosphate, respectively. When 
ground and heated in a dark room the Ciply phosphate shows the same 
phosphorescence as the Spanish phosphorite, but in a less degree. The 
nodule bed is very continuous at the base of the Tufeau de Ciply, 3 but 
is generally in such a thin sheet that it does not pay to work it. Oc- 
casionally, however, it has been collected in pockets on the surface 
of the underlying bed, to such an extent that it has been mined with 
profit. Such is the case in Cuesmes and Ciply, where openings have 
been made and large quantities of phosphate taken out. The thickness 
of the bed is very variable, ranging generally from a few inches to 3 
feet. The underlying bed is much worn and eroded on the top. 4 
It is from the bed immediately underlying the Ciply Conglomerate 
that over nine-tenths of the phosphate now mined in Belgium is obtained. 
This bed is known as the Craie Griseor Craie Brune, and comes between 
the Ciply nodule bed and the White Chalk (Craie Blanche). It is of a 
very variable thickness, being in some places entirely eroded, so that the 
Ciply Conglomerate comes in direct contact with the White Chalk. At 
other localities it reaches a very considerable thickness, as near the town 
of Ciply, where it is 30 meters deep. The bed consists of a coarse- 
grained rock, easily crumbled in the fingers, softer at the top than at 
the bottom, and of a gray or brown color. It is formed of a mixture of 
grains of carbonate of lime and small pebbles of phosphate of lime, 
about the size of a pin head. The proportions of the two constituents 
'Cornet and Briart: Bull. Acad. roy. Belgique, 2d series, vol. 37, 1844, pp. 338,844. 
2 F. L. Cornet: Bull. Soc. geologtque France, 3d scries, vol. 2, 1874, p. 570. 
3 Mr. Melsens: Bull. Acad. roy. Belgique, 2d series, vol. 38, 1874, pp. 25-52. 
4 F. L. Cornet: Bull. Soc. g6ologique France, 3d series, vol. 2, lb74, pp. 567-577. 
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