. First[-fourth] annual report of the Geological survey of Texas, 1889[-1892] Edwin T. Dumble, state geologist. have been least disturbed bymore recent uplifts, as in parts of the Babyhead region, and perhaps also in the BurnetCounty tract between Spring Creek and Clear Creek, it is probable that excellent speckledand mottled varieties may be obtained. These will frequently polish with good effect, andsome outcrops show by their style of weathering that certain oxidation tints of value forornamentation may be utilized. In working this class, however, great care will be necessaryto select only
. First[-fourth] annual report of the Geological survey of Texas, 1889[-1892] Edwin T. Dumble, state geologist. have been least disturbed bymore recent uplifts, as in parts of the Babyhead region, and perhaps also in the BurnetCounty tract between Spring Creek and Clear Creek, it is probable that excellent speckledand mottled varieties may be obtained. These will frequently polish with good effect, andsome outcrops show by their style of weathering that certain oxidation tints of value forornamentation may be utilized. In working this class, however, great care will be necessaryto select only those qualities in which the mica is well distributed and in comparatively finescales. Otherwise serious blemishes may result from irregularity of weathering. Eorpaving blocks, foundation stones, and special uses much of this material may be utilizedeventually at little cost. These remarks apply with equal force to a large area in northeastern Ma-son County, which I have examined in detail only within the last few Llano County there is a very fine-grained red-speckled gneiss of this va- .?:,.:. BUILDING STONES. 641 riety in Millers Creek, southeast of Lone Grove, which may be worthy ofinvestigation. In Yoakum Hollow similar outcrops occur, and a variety ofthis class is favorably exposed in the Cat Mountains. Four miles north of eastfrom Enchanted Rock, and in much of the surrounding area, some very choicematerial of the kind may be mined, as well as southward in the northernportion of Gillespie County. THE COMPRESSED GRANITES. There are many of the Archean granites which appear as if tightly wedged in between theadjoining strata, although the result is perhaps more often due to the expansion produced bythe crystallization of the magma. For this last reason the material is frequently an aggrega-tion of large interlocking crystals, without coherence enough to render the rock useful forany purpose where stress is anticipated. Occasionally some very fine crystals of ortho
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