The Chief Commercial Granites of Massachusetts, New Hampshire and Rhode Island

30 feet accessory minerals ægirite air compressor capacity air hand tools air per minute air plug drills allanite apatite biotite biotite black mica black silicates calcite CaO lime cent of CaO chlorite constituents crystals cubic feet cutting shed dark derricks descending order diabase diameter dike east epidote Estimated mineral percentages feet in depth feet of air feet thick flow structure gneiss grain as vertical Granite Company granite specimen greenish hematite hoisting engines hornblende inches thick kaolinized limonite magnetite Mass medium to coarse microcline miles millimeter monuments oligoclase order of abundance orthoclase pegmatite pegmatite dikes pinkish plant consists porphyritic potash feldspar microcline pyrite quarry quartz monzonite Railroad Redstone riebeckite rift and grain rift is reported rock Rockport Rosiwal method Rusty stain secondary sets of joints sheet structure smoky quartz spaced steam drills steam pumps stone striking texture thin section West Quincy Westerly white mica XXVIII zircon