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ARAGONITE.

This mineral was found by me in only two localities in sufficient quantity to be of any use; yet I do not doubt that it can be found in other localities equally as abundant as at the places mentioned below.

One of these places is on the lands of Mr. D. N. McRea, about fifteen miles west of the town of Lampasas, near the north line of Burnet County. It occurs in a fissure in the massive limestone of the Carboniferous formation. It is very compact and much of it is beautifully banded. Some of it when fractured has a dark resinous color. It takes an excellent polish, and can be obtained in slabs large enough for table tops.

Another locality is in San Saba County, on the south side of Cherokee Creek, five or six miles from its mouth. This has about the same geological position as at the former locality, and the material is about the same as that from Lampasas County, only it seems to be a little whiter and the crystals are smaller. This material is used largely for making ornaments, and is generally known when polished as "Mexican onyx." It is not an onyx, but is simply a carbonate of lime crystalized under a peculiar form. It does not differ in composition from calcite.

STRONTIANITE.

This mineral is found in beautiful crystals on the head of Little Lucy Creek, six miles north of the town of Lampasas, and elsewhere in that vicinity. It also occurs at the head of Lynch's Creek, twelve miles northwest of the town of Lampasas.

At both these places it is imbedded in the limestones of the Cretaceous formation. It is found on Lucy Creek at two horizons about twenty feet apart. In the lower it is in massive nodular form, and is in a bluish limestone. At the upper horizon it occurs in geodes, with crystals of dog-tooth spar. Some of the crystals are beautifully tinged with blue, and are almost perfect crystals. Other crystals are clear white. This mineral is used in the manufacture of nitrate of strontia, which is used for making red color in fireworks. One nodule was obtained weighing forty-three pounds.

Another locality where this mineral was seen was near the head of Lynch Creek. It occurs in this place also in the Cretaceous formation, and is associated with crystals of calcite. None of the material at this place had the beautiful blue tinge that gives value to the crystals for cabinet specimens. It is probable, however, that such crystals might be found upon diligent search.

BUILDING STONE.

There is an abundance of building stone in all the counties, and in nearly