Ch. 3: Precious Gem stones in 1913

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	GEMS AND PRECIOUS STONES. 659 tites in this hill, but most of the tourmaline is dark green or nearly-black. Among other minerals associated with the beryl are amblygo-nite, clevelandite, muscovite, arsenopyrite or lollingite, and cassiterite. MASSACHUSETTS. Beryl of especially fine quality has been mined at Beryl Hill, 2-1/2 miles N. 68° E. of Royalston, Mass., by F. H. C. Revnolds, of Boston. Beryl Hill is a low, flat topped hill partly cleared for pasture on the summit and west side. Five openings have been made, four on the summit and one a short distance below, on the west side. The openings are on two approximately parallel outcrops of pegmatite about SO yards apart extending in a northwest direction across the summit of the hill. A small glacier-made depression lies between the two outcrops. Two pits are located on the pegmatite on the southwest, one at the brow of the hill and the other on the slope about 30 yards northwest. This pegmatite outcrops for about 100 yards southeast to the opposite side of the summit. The northeast pegmatite outcrop extends 100 yards from a pit on the east side of the hill across the summit to a trench on the west side with another pit between these. From the trench the outcrop extends more than 100 yards about N. 20° W. along the edge of the hill. None of the openings are large, the deepest being only 12 feet deep and the largest a shallow french 60 feet long.

	the country rock is chietly mica gneiss cut by biotite granite, the strike of the gneiss varies from northwest to N. 15° E. and the dip is also variable. The relation between the mica gneiss and granite are not well exposed in the workings, but the granite appears to merge into the pegmatite in places. In one of the openings biotite diorite is in contact with the pegmatite and granite. The texture of the pegmatite ranges from that of coarse granite to rock in which the individual minerals are more than a foot across. Most of the feldspar of the pegmatite is the buff-colored to pink potash variety, but some slbite is present. Some of the feldspar occurs in rough crystals and other is graphically intergrown with quartz. Much of the quartz occurs in light smoky^r gray^r masses or segregations. Among other minerals of the pegmatite besides beryl are muscovite in crystals up to 3 inches across, a little biotite, black tourmaline, and dark-red jarnets.

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