Chapter III.

Building Stones.  (pp. 69-91)

“Under this term are included all stones for ordinary masonry construction, as well as for ornamentation, roofing, and flagging.  The number of different kinds used is very great, and includes practically all varieties of igneous, sedimentary, and metamorphic rocks, but a few stand out prominently on account of their widespread occurrence and durability.

“The cost of a building stone naturally exerts decided influence on its use.  Since the ease of splitting and dressing a stone influences its cost, the texture is also of importance.  Color is another factor in determining the value of a building stone, and this, together with other considerations, sometimes gets a fashion leading to the widespread use of certain stones.  This has been well illustrated in the eastern cities of the United States where, for many years, Connecticut browstone (sic) was in such great demand for use in building private dwellings that much inferior stone was put on the market.  More recently Indiana limestone and Ohio sandstone have met the popular fancy, and these two are now used in vast quantities (circa 1905)....”  

Granites.

“Characteristics of Granites...As commonly used by quarrymen, the term granite includes all igneous rocks and gneiss; but in this book it is used in the geological sense, which is more restricted.  From the geological standpoint a granite is a holocrystalline, plutonic igneous rock consisting of quartz, orthoclase feldspar, and either mica or hornblende, or both.  There are also varying but usually small quantities of other feldspars, and there may be subordinate accessory minerals, such as pyrite, garnet, tourmaline, and epidote.

“Granites vary in texture from fine to coarse grained, and in some cases are porphyritic.  They pass into gneisses by such insensible gradations that no sharp line can be drawn between the two.  In color they vary, being, most commonly gray, mottled gray, red, pink, white, or green, according to the color abundance of the component minerals.  Most granites are permanent in their color, but some of bright red color bleach on exposure to weather....”

“Distribution of Granites in the United States...Granite usually occurs in great bosses frequently forming the cores of mountain chains.  Removal of the overlying strata by denudation has revealed the granite, which, owing to its greater durability, is often left standing as peaks or domes by the farther removal of the surrounding, weaker strata.  Granites show a wide, geologic range, but most known occurrences are associated with the older formations.

“Granite forms an important source of durable building stone widely distributed in the United States (Fig. 20); but nearly 70 per cent of that quarried comes from the Atlantic states....”

“Central States. - In these states there are several widely separated areas:  (1)  the Minnesota-Wisconsin area (35), affording many fine stones;  (2)  the southeastern Missouri area;  (3)  east central Arkansas; and  (4)  Llano County, Texas, all supplying stones of excellent quality....”

“Use of Granite. - On account of its massive character and durability, granite is much employed for massive masonry construction, while some of the granites that take and preserve a high polish, and are susceptible of being carved, are in great demand for ornamental and monumental work.  Because of its greater durability, granite has in recent years (circa 1905) largely replaced marble for monumental purposes.

“The refuse of the quarries is often dressed for paving blocks or crushed for roads and railroad ballast.  The size of the blocks which can be extracted from a granite quarry depends in part on the spacing of the joint planes, in part on the perfection of development of the rift, some of the monoliths that have been quarried being of immense size; for example, one from Stony Creek, Connecticut, measured 41 ft. x 6 in. x 6 in..; one from Vinal Haven, Maine, 60 ft. x 5 ½ ft.; one from Barre, Vermont, 60 ft. x 7 ft. x 6 ft....”

Limestones and Marbles.

“General Characteristics...A great series of sedimentary and metamorphic rocks, composed chiefly of carbonate of lime, or, in the case of dolomite, of carbonate of lime and magnesia, is included under the term limestone and marble.  These rocks also contain varying, but usually small amounts of iron oxide, iron carbonate, silica, clay, and carbonaceous matter.  When of metamorphic character, various silicates, such as mica, hornblende, and pyroxene, may be present.

“These calcareous rocks vary in texture from fine-grained, earthy, to coarse-textured, fossiliferous rocks, and from finely crystalline to coarsely crystalline varieties.  There is, also, great range in color, the most common being blue, gray, white, and black, but beautiful shades of yellow, red, pink, and green, usually due to iron oxides, are also found.  Their crushing strength commonly ranges from 10,000 to 15,000 pounds per square inch, while their absorption is generally low.

“The mineral composition of limestone exerts a strong influence on its durability.  Those limestones which are composed chiefly or wholly of carbonate of lime are liable to solution in waters containing carbon dioxide; but dolomite limestones, especially coarse-grained ones, disintegrate rather than decompose.  Streaks of mineral impurities cause the stone to weather unevenly.  Pyrite is an especially injurious constituent, not only on account of its rusting, but also because the sulphuric acid set free by its decomposition attacks the stone.  Black or gray limestones will sometimes bleach on exposure.

“Varieties of Limestones. - In the geological sense limestones are of sedimentary origin, while marbles are of metamorphic character, but in the trade the term marble is applied to any calcareous rock capable of taking a  polish.  In addition to the different varieties of marble and the ordinary limestones there are certain kinds of calcareous rock to which special names are given, as follows: -

“Distribution of Limestones in the United States. - Limestones are found in many states, and in all geological formations from Cambrian to Tertiary, but those of the Paleozoic, which are much used in the Eastern and Central states, are more extensive and more massive than those of later formations.  Although many large quarries have been opened to supply a local demand, the product is shipped to a distance from only a few localities.  At present (circa 1905) the sub-Carboniferous Bedford (18) oölitic limestone of Indiana (Pl. VI) is, perhaps, the most widely used limestone in the United States.  It occurs in massive beds from 20 to 70 feet thick, and is said to underlie an area of more than 70 square miles.  Although soft and easily dressed, it has good strength, and has been used in many important cities of the United States.

“Cretaceous limestones are worked in Kansas, Nebraska, and Iowa, although the most important sources are in the Paleozoic formations....”

Sandstones.

“General Properties...While most sandstones are composed chiefly of quartz grains, some varieties contain an abundance of other minerals, such as mica, or, more rarely, feldspar, which in rare cases may even form the predominating mineral.  Pyrite is occasionally present, and varying amounts of clay frequently occur between the grains, at times in sufficient quantity to materially influence the hardness and dressing qualities of the stone.  The hardness of sandstones, however, usually depends on the amount and character of the cement, varying from those having so small an amount of silica or iron oxide cement that the stone crumbles in the fingers to those quartzites whose grains are so firmly bound by silica that the rock resembles solid quartz.  With these differences the chemical composition varies from nearly pure silica to sandstone with a large percentage of other compounds.  (For analyses, see Kemp’s “Handbook of Rocks.”)

“There are many colors among sandstones, but light gray, white, brown, buff, bluish gray, red, and yellow are most common.  In density sandstones range from the nearly impervious quartzites to the porous sandrocks of recent geologic formations, and consequently they show a variable absorption.  Most sandstone contain some quarry water, and those with appreciable amounts are softer and more easy to dress when first quarried; but they cannot be quarried in freezing weather.  The average specific gravity of sandstone is 2.3, and accordingly a cubic foot weighs about 140 to 150 pounds.

“On the whole, sandstones resist heat well and are usually of excellent durability, since they contain few minerals that easily decompose.  When they disintegrate it is commonly by frost action.  The injurious minerals are pyrite, mica, and clay.  Pyrite is likely to cause discoloration on weathering; the presence of mica tends to cause the stone to scale off if set on edge; and clay may cause injury to the stone in freezing weather on account of its capacity for absorbing moisture.  The value of a sandstone is often lessened by careless quarrying, or by placing it on edge in the building, thus exposing the bedding planes to the entrance of water.

“Varieties of Sandstone. - With an increase in the size of their grains, sandstones pass into conglomerates on the one hand and with an increase in clay into shales.  By an increase in the percentage of carbonate of lime they may also grade into limestones.

“On account of these variations, as well as the difference in color and the character of the cement, a number of varieties of sandstone are recognized, of which the following are of economic value:  arkose, a sandstone composed chiefly of feldspar grains; flagstone, a thinly bedded, argillaceous sandstone used chiefly for paving purposes; bluestone, a flagstone much quarried in New York; freestone, a sandstone which splits freely and dresses easily; brownstone, a term formerly applied to sandstones of brown color, obtained from the eastern Triassic belt, and since has come to have a geographic meaning and no longer refers to any specific physical character.

“Distribution of Sandstones in the United States. - Sandstone occur in all formations from pre-Cambrian to Tertiary.  They are so widely distributed that for local supply there are numerous small quarries in many states, but there are several areas which have been operated on an extensive scale, some of them for many years.  Of these, one of the best known is the Triassic Brownstone belt, which extends from the Connecticut Valley in Massachusetts southwestward into North Carolina.

“Among the Paleozoic strata there are many sandstones, often massive, and usually dense and hard.  Of these the Medina and Potsdam are specially important and much quarried in New York State (27, 28).  The same formations extend southward along the Appalachians and are available at several points.  Devonian flagstones are extensively quarried at several localities in New York and Pennsylvania.  At the present time (circa 1905) the Lower Carboniferous Berea sandstone of Ohio (29) is in great demand because of its light color, even texture, and the east with which it is worked.  Moreover, it has the peculiar property of changing to a uniform buff on exposure to the air.  There are numerous other Paleozoic sandstones in the central states, among them the Potsdam which covers a wide area in Michigan and Wisconsin (35).  some of this stone is bright red in color.

“The Mesozoic and Tertiary strata of the West contain an abundance of sandstone strata, and quarries often in many of them yield a good quality of stone.  Though usually less dense and hard than the Paleozoic sandstones, they serve admirably for buildings in the mild or dry climates of the West.

“Uses of Sandstones. - The wide distribution of sandstones makes them an important source of local structural material.  They are chiefly used for ordinary building work, and but little for massive masonry or monuments.  The thin-bedded flagstones are much used for flagging, and some of the harder sandstones are split up for paving blocks.  For other uses, see Abrasives....”

Chapter V.  Lime and Calcareous Cements  (pp. 109-123)

“Composition of Limestones (35). - Limes and calcareous cements form an important class of economic products, obtained from limestones by heating them to a temperature ranging from that of decarbonation to clinkering.  The term limestone is applied to one of the main divisions of the stratified rocks so widely distributed, both geologically and geographically, and formed under such different conditions, that its composition varies greatly, this range of variation becoming appreciable from an inspection of the following table, which contains a few selected types:* -

(* Page 109 footnote:  Kemp, “Handbook of Rocks.”)

“From this table it will be seen that limestones vary from rocks composed almost entirely of carbonate of lime, or of carbonate of lime and carbonate of magnesia, to others which are high in clayey or siliceous impurities.  The presence of such impurities in large quantity usually imparts an earthy appearance to the limestone, and sometimes even gives it a shaly structure.

“Marked variations in composition may at times be found even in a single quarry, while in other cases a limestone formation may show remarkable uniformity of composition over a wide area.

“Changes in Burning (8, 35). - When limestones are calcined or ‘burned’ to a temperature sufficiently high to drive off volatile constituents, such as carbon dioxide, water, and sulphur (in part), or, in other words, to the point of decarbonation, the rock is left in a more or less porous condition.  If heated to a still higher temperature, the rock clinkers or fuses incipiently, but the temperature of clinkering depends on the amount of siliceous and clayey impurities in the rock.

“Limes (5, 8). - Limestone free from or containing but a small percentage of argillaceous impurities is, by decarbonation, changed to quicklime, a substance which has a high affinity for water, and which, when mixed with water ‘slakes,’ forming a hydrate of lime.  This change is accompanied by the evolution of heat and by swelling, and this action becomes the more marked the higher the percentage of lime carbonate in the rock, for the slaking activity is retarded by the presence of magnesium carbonate, and especially by argillaceous impurities.  Limes have, therefore, been divided in ‘fat’ limes and ‘meager’ limes, depending on the rapidity with which they slake and the amount of heat they develop in doing so (5).

“Hydraulic Cements. - With an increase in clayey and siliceous impurities, the burned rock shows a decrease in slaking qualities, and develops hydraulic properties, or sets when mixed with water, and even under the same.  Products of this type are termed cements, and owe their hydraulic properties to the formation during burning of silicates and aluminates of lime.  On mixing the burned ground rock with water, these take up the latter and crystallize, thereby producing the set of the cement.

“Hydraulic cements can be divided into the following classes:  Pozzuolano cements, hydraulic limes, natural cements, and Portland cements....”

“Distribution of Lime and Cement Materials in the United States.  Limestone for Lime. - Limestones of suitable composition for burning lime are so widely distributed that no particular regions or states require special mention.  In the New England states, crystalline limestones are the chief source of supply.  In the Appalachian states, from New York to Alabama, there are many Paleozoic limestones of high purity, notably the Trenton, Lower Helderberg, and Carboniferous limestones (see state references).  The same series of rocks are also of importance in the Mississippi Valley states from Tennessee to Michigan (27).  Lime of excellent quality is obtained from the Subcarboniferous in Iowa (41), Kansas (21), and Missouri (41), and from the Cretaceous in Texas (41).  Limestones suitable for lime manufacture are also found in numerous localities in the Pacific cast states (41).

“Hydraulic Limes. - Largely because of the great abundance of natural rock cements, which are of superior value, these materials, though much used abroad, are of no importance in the United States.

“Natural Rock Cements (1, 41). - Calcareous rocks of this class are found at a number of points, mainly in the Paleozoic formations.  In 1903 they were worked in sixteen different states, eleven of which are east of the Mississippi.  These are found at a number of points in the Appalachian region, but owing to the folded character of the beds (Pl. X, Fig 1), their extraction is often difficult.  The most important natural rock cement region of the United States is that of Rosendale, New York (32, 35), where the cement rocks are found in the Water Lime beds at the base of the Lower Helderberg....”

“Cement rock is also obtained in southeastern Ohio (36); at Louisville, Kentucky (23), probably the second most important center in the United States; in the Hamilton rocks at Milwaukee, Wisconsin (44); and at Utica and LaSalle, Illinois (17), where it is found in the Calciferous formation in a bed from 6 to 8 feet thick.

“Portland Cements. - Clay and limestone, in one form or another, are so widely distributed throughout the United States, that it is possible to manufacture Portland cement at many localities, and the geologic age of the materials used ranges from Ordovician to Pleistocene (41).  Nineteen states were making this cement in 1903, the factories being spread over the country from the Atlantic to the Pacific (41).

“By far the most important district is the Lehigh Valley in Pennsylvania, which supplies about 70 per cent of the domestic product...The same beds are found in the adjacent territory of New Jersey (30)....”

“Uses of Lime. - The most important single use of lime is for mixing with sand to form mortar, and many thousands of tons are used annually for this purpose.  In addition to this use, lime is employed for a great variety of purposes, of which the following are the most important:  as a purifier in basic steel manufacture; in the manufacture of refractory bricks, ammonium sulphate, soap, bone ash, gas, potassium-dichromate, paper, pottery glazes, and calcium carbide; as a disinfectant; as a fertilizer; as a polishing material; for dehydrating alcohol, preserving eggs, and in tanning.

“Uses of Cement. - The use of hydraulic cement is constantly increasing in the United States, this being specially true of Portland cement, which is superseding natural cement to a great extent, and is finding an increasing use in building and engineering operations.  For pavements, Portland cement is probably more extensively used in America than in any other country (circa 1905); and as an ingredient of concrete it is widely employed.  Blocks weighing as much as 65 to 70 tons have been made for harbor improvements at New York City (37 a)....”

Chapter IX.  Abrasives  (pp. 158-166.)

“Introductory. - Under this heading are included natural products employed for abrasive purposes; but brief reference will be made to some artificial compounds which come into serious competition with the natural ones.

“The natural abrasives may be divided into the three following groups:  (1)  those, like grindstones, whetstones, and Buhrstones, which occur in the form of massive rock, and which can consequently be cut and manufactured directly into the desired shape;  (2)  those, like garnet, emery, quartz, and corundum, which occur usually as grains in a rock or vein, and which have to be separated mechanically from the rock; and  (3)  those, like infusorial earth, quartz sand, and pumice dust, which occur in more or less unconsolidated condition.

“While some abrasive substances occur as constituents of veins, the great majority form a part of rocks of either sedimentary, igneous, or metamorphic origin.  That they are widely distributed both geologically and geographically is shown in the following description of the individual groups, and the map (Fig. 31): -

“Grindstones (3, 3). - These are made from sandstones of homogeneous texture and sufficient cementing material to hold the quartz grains together, but not enough to so fill the pores as to make the rock wear smooth under use.  Most of the grindstones produced in the United States are obtained from the Berea grit of Ohio (Pl. XIII, Fig. 1) and Michigan, certain layers of which are highly prized for this purpose.

“Pulpstones, which have a diameter of 48 to 56 inches, a thickness of 16 to 26 inches, and a weight of 2300 to 4800 pounds, are a thicker variety of grindstone.  They are used for grinding wood pulp in paper manufacture, and hence have to withstand continual exposure to hot water.  On account of their superior quality, pulpstones from Newcastle-upon-Tyne, England, supply most of the American Demand (circa 1905); but it is probably that certain beds of the Ohio sandstones will be found suited for this purpose (3)....”

“Production of Abrasives. - The value of the abrasives produced in the United States during the last three years, together with the imports and artificial abrasives, was as follows: