On the Economical Uses of some species of Testacea. 235 



The coccolite, of a deep green color, occurs in masses of large 

 granular concretions, and in grains disseminated through the quartz, 

 presenting in its fracture, brilliant cleavage faces, partially developing 

 the primary form. The coccolite encloses rhomboidal calc spar of 

 various hues ; and on blasting to obtain unweaihered specimens, the 

 rock opened through several veins of Tabular Spa?', which remained 

 on either face, coating it with a thin layer of most delicate whiteness. 

 Crystals of prismatic green pyroxene, an inch in length, were ob- 

 served in one instance. 



In a large boulder, (near the road on the right, just before entering 

 the village of Boonville from the south,) some thirty feet in circumfer- 

 ence, and eight or ten feet in height, were several veins of white feld- 

 spar and quartz, from two to five inches wide, intersecting each other 

 and extending through the rock, which contained in profusion the 

 brown granular garnet, and a few points of the green coccolite. 

 These minerals were noticed in Vol. xiii. p. 198, and richly deserve 

 for their beauty the high encomiums there bestowed ; and the fact last 

 mentioned illustrates the uniformity which prevails in the associations 

 of minerals, being the same as found at Willsboro' and other places. 



Art. III. — On the Economical Uses of some species of Testacea. 



(Concluded from No. I. page 73.) 



VI. MuREx ? (Linn.) — Hebrew Argaman. Greek IIoq- 



cpvga, and Lat. Purpura. Purple WhelJc. 



What the species was from which the ancients obtained the real 

 Tyrian dye, is now uncertain, bbt in coloring cloth there is no doubt 

 that many species, and perhaps two or three genera, were used. 

 The Murices, the Buccina, and the Stromhi, and probably most of 

 the voluted univalves, contain more or less of the coloring matter, 

 and we may reasonably suppose that they would not be neglected 

 where there was so great a demand for the purple dye. By the old 

 writers, however, they are all described under one name. Pliny 

 makes mention of two species, from one of which only the true color 

 was obtained ; the other (which he calls Conchylium) seems from 

 his description to have been a real Buccinum, and produced only 

 a poor blue or greenish hue, like the sea in a storm, while it emitted 

 a strong rank smell, and was of course less valuable. The shell dye 

 has been in use from the earliest periods. Moses, B. C. 1491, 



