ANALYSIS

Silica. (SI O2) 25.76%
Alumina, (AL2 O3) 10.41%
Iron, (FE2 O3) 4.85%
Lime, (CA O) 33.80%
Magnesia, (MG O) 13.33%
Sulphur, (SO3) 1.30%
Carbon dioxide, (C O2) 6.84%
Potassium, (K2 O) .43%
Sodium, (NN2 O) .60%
Moisture, (Red heat) 1.92%
Loss, .66%
———–
100.00%

The following is from a very elaborate Consolidated Rosendale Cement Company (CRCCo) advertising book published around 1910. The CRCCo was incorporated in 1902 when Samuel D Coykendall and other investors purchased the mines, factories and brand names of several cement companies. The book cover, grey-green card stock, is inscribed in white lettering “With the Compliments of the, Consolidated Rosendale Cement Co., 26 Cortland Street, New York”. There are three pages of text, photos of the interior of a cement mine, a bank of kilns, three of the company’s mills, the wharves in Eddyville, the loading Dock on the Company’s Canal (formerly the Delaware & Hudson Canal) in Rosendale, the Brooklyn Bridge and 44 buildings built with CRCCo cement.

Before showing a few cuts of prominent buildings in which “Genuine Rosendale Cement” was largely used, a word as to the way in which it is mined and prepared for the market may not be amiss. The cement sold in this country for building purposes is of two kinds: Portland, which is an artificial cement, and Natural Cement made of the natural rock. The natural cement, as manufactured in the Binnewater section of Rosendale, has long been famous. The deposit from which our cement is made is a magnesian limestone or cement rock, bluish gray in color, and is found in strata from fourteen to twenty feet in thickness in the neighborhood of Rosendale in Ulster County, in the State of New York. These strata have different inclinations to the horizon, the face of the country indicating violent upheavals, some of which evidently took place while the cement stone was in a plastic form. Geologists claim that the rock is one of the lowest of the various limestone deposits in America, and without doubt was formed from the shells of extinct marine animals, as what is known as the middle rock or layer abounds in various fossils indicating that the now solid stone once was the soft ooze of the ocean bottom.

The cement is high in magnesia, differing from Portland, which cannot contain over 3 1/2%, while Rosendale contains from 12% to 15%. A prominent member of the American Society of Civil Engineers writes as follows: “With respect to magnesia in natural cements it may be interesting to note here of its successful use in these Rosendale Cements, that calcined magnesia has decided hydraulic properties, hardening in water to a stonelike mass. But this ready hydration and combination of the magnesia only takes place when the rock is lightly burned. When hard burned the magnesia becomes sluggish and hydrates with extreme slowness. The condition, then of its successful use is light burning.” This is the precaution observed in our Rosendale factories,. All hard burned clinkered lumps are carefully picked out by experts and discarded as waste. Thus made, Rosendale Cements have successfully been employed for many years in many important structures.

Another prominent engineer says:  “Magnesia is a suitable ingredient of mortars to be immersed in sea water, if it can be obtained at a cost that would permit its application to such purposes the problem of making concrete unalterable by sea water would be solved.”

In the winter of 1875-6 it became necessary to rebuild a portion of the sea wall of a cover face at Fort Taylor, Key West, Fla., which had been carried away in the hurricane of September 13th and 14th, 1875. Rosendale Cement was used for the work. Many years afterward the U.S. Officer, who was in charge of the work at the time of the repairs, wrote to the overseer of the work regarding the condition of the wall, and received the following reply: “It stands as firm as the hills, although the earth and regular filling in the rear have long since been washed away, leaving the sea wall unsustained to stand the pelting of the sea.”

QUARRYING

The process of manufacturing consists in quarrying the stone with explosives. The rock is taken from separate galleries, corresponding with the various strata or layers. There are two such strata which are available in the manufacture of high grade cement —– the upper and lower. The Middle layer contains impurities and is not used in first-class cements.

The stone taken from the quarries is broken into spawls of about half a cubic foot each, loaded upon small cars, and then transported to the kilns where it is burned.

KILNS

The calcined product is carefully examined by experts whose time is devoted to that branch of the manufacture, the over-burned and under-burned stone is removed and the properly burned product conveyed to crackers, where it is reduced to a suitable size for grinding; it is then sent to the mills, where it is reduced to a proper fineness, then conveyed to the packers and fed into the package required —– either wood, cloth or paper. Barrels contain 285 lbs.: (three cloth bags or four paper bags equal one barrel) —– and is then ready for delivery.

MILLS

Our mills have a daily capacity of over 10,000 barrels. As our storage facilities are large, we always have a large stock of cement on hand, and thus can fill all orders promptly. The situation of our mills and storehouses affords us ample rail and water connection for all points.

The first genuine Rosendale Cement was made of the stone discovered at Rosendale, during the opening of the Delaware & Hudson canal in 1823, and was used in the masonry of the locks and bridges of the canal. It may be well to add that as the present owners of the canal we recently had occasion to make repairs, which necessitated the cutting away of a portion of one of the bridges in the construction of which the cement had been used, and we found the cement as hard as the stone.

There are other cements made in various parts of the country, and branded “Rosendale” by their manufacturers. These cements do not possess the important and essential qualities which make genuine Rosendale popular with consumers, viz: a moderately slow set after mixing, allowing the mortar to be used slowly without fear of undue setting, thus making it possible to do much quicker work in laying masonry than can be done with the short, quick-setting cements made in the districts outside the Rosendale

neighborhood, as the quick-setting necessitates constant re-tempering. In addition to these qualities the color of Rosendale Cement is a rich, dark brown, that gives to the joints of the masonry where it is used a handsome and clearly defined outline, greatly to be desired where fine work is demanded.