Brownstone, although not yet officially recognized as the state rock*, is a type of sandstone, that forms from the cementing together of sand grains. The example seen here dates back approximately 210 million years to the Late Triassic Period, the early days of the dinosaurs. It formed from sand deposited by rivers in a desert environment.
Brownstone was used as a building stone in thousands of houses, apartments, churches, libraries, bridges, and train stations built in the northeastern United States between the early 1700's and about 1900. New Jersey was the nation's most important producer of brownstone and supplied most of the material used in New Jersey, New York, and Philadelphia.
* In order to become "official", the state Legislature has to adopt the item and sign documentation to acknowledge such recognition.
BROWNSTONE INDUSTRY OF NEW JERSEY
Brownstone is a reddish-brown sandstone used extensively as a building stone in eastern United States during the nineteenth century. Its place in geologic history, however, dates back to late Triassic and Early Jurassic times, about two hundred million years ago when the dinosaurs were establishing their domination over the lands. During this time, rivers poured sand-laden water far and wide over lowland plains of central New Jersey. Subsequently the quartz grains, in company with particles of orthoclase feldspar and sometimes muscovite mica as well, were transformed by natural cementation into sandstone. This hardening process was accomplished by the mineral hematite, a red oxide of iron, which not only bound the sand particles together but imparted the characteristic color as well. Because of its feldspar content, geologists refer to this rock as an arkose, or arkosic sandstone. In New Jersey, these sandstones occur in the Stockton and Passaic Formations.
In colonial times the Stockton was recognized as the best building stone obtainable in the Delaware Valley, and it was this sandstone which was chosen for Nassau Hall, completed in 1756 at Princeton University. Brownstone quarried from the Passaic Formation near Newark likewise served as a building stone beginning early in the history of European settlement of our country. Old First Presbyterian Church, dedicated in 1791 and for many years the largest church in New Jersey, was built of this stone.
During the first half of the nineteenth century, sandstone quarries were opened in a great many places throughout central New Jersey, furnishing handsome brownstone fronts for houses and public buildings. All of these quarries were advantageously located for transportation of the stone by railroad or canal. Near Princeton and from the vicinity of Trenton northward to Raven Rock, quarries along the Delaware and Raritan Canal in the Stockton Formation supplied an excellent building stone. Many thousands of tons were quarried annually. Even so, the demand exceeded supplies.
Quarries in thick beds at Little Falls produced a superior, fine grained red sandstone that was, due to its deep, rich hue, dubbed "liver rock" by local workmen. Shipped via the Morris Canal, this stone was used in the construction of mansions and churches in Paterson, Newark and New York City. In addition, statues of our former state governors and other notables were occasionally sculpted from this rock.
Quarries in the Belleville area near Newark, however, were the most productive, supplying more material for brownstone fronts of houses than any other source in the country. A light chocolate brown sandstone found here was noted for its capacity to rub down to smooth faces. Old Queens, completed in 1809 at Rutgers University, was built of Belleville brownstone from the Passaic Formation.
By mid-century many of the quarries, especially in the vicinity of Newark, had been abandoned as cities expanded and land became more valuable. Public buildings continued to be built of brownstone, but not as frequently as before. By the turn of the century, quarrying was on a much smaller scale with most brownstone now going into foundation work and windowsills of brick buildings. Thus, after some two hundred years of popularity, the brownstones of New Jersey, and the era they so graciously represented, receded into history.
Brownstone Industry of New Jersey; Written by James S. Yolton. Professor Emeritus of Geology. Upsala College. ca. 1960, R9/93. R10/98.
New Jersey also has an official state dinosaur; Hadrosaurus foullki, the fossil skeleton that was discovered in Haddonfield in 1858. To learn more about the official state symbols, click HERE.
Samples of brownstone and sixteen other New Jersey rocks and sediments are available for purchase. For more information, click HERE.
There are two contenders for the title of "State Mineral", to read about them click HERE.
New Jersey Geological Survey
NJDEP, PO Box 427
Trenton NJ 08625