What is Brownstone?
Brownstone is a word used to refer to both a type of building material and structures built in it. This material was at one point used all over the world in construction. Its popularity as a building material started to go down when builders began to realize that it weathered poorly, and that other materials might be more suitable.
The building material is a type of sandstone, which was deposited in Massachusetts, Connecticut, and New Jersey during the late Triassic period. From 245 million to 208 million years ago, vast beds of rock were being formed. Near the end of this period, the only formation of Eastern North America was deposited in downfaulted troughs. Where waters had been, upheaval created marshes and fens where dinosaurs roamed and cycads grew. Sand and silt collected in huge basins and time, with the assistance of pressure, began the relentless work of compressing these grains into rock. Brownstone is a product of this time.
Characteristics of Brownstone
Brownstone is composed from consolidated sand bound together by a cement of iron oxide. This iron oxide gives brownstone its characteristic color; it can have a gray, blue, pink or purple hue when other materials are present (feldspar, aluminum, magnesium, etc). The mica embedded in the brownstone quarried at Portland, Connecticut, appears to be unique to that area and gives it a distinctive glitter. Due to its sedimentary formation, brownstone has a rounded grain, although at times it can be quite angular. When the grain of the stone is rounded and the interstitial cement is not too cohesive it does not tend to cleave or fracture in a given direction as does diamond for example. This stone is commonly called freestone because it can be worked freely in every direction, a characteristic that made it popular with stone cutters and masons.
Portland Brownstone
The brownstone for the S&SM arch comes from the Portland Brownstone Quarry. The brownstone mined from these quarries was an important source for construction in the latter half of the 19th century. The stone from these quarries was used in a number of landmark buildings in Chicago, Boston, New York City, Philadelphia, New Haven, Connecticut, and Hartford, Connecticut. The site was listed as a National Historic Landmark, which placed it on the National Register of Historic Places, on May 16, 2000
Old Photo of the Brownstone Quarry (New York Public Library)
History of the Arch
The arch was designed by Hartford architect George Keller, whose ashes were buried in the east tower when he died in 1935, along with those of his wife, Mary, who died in 1946. The arch was dedicated on September 17, 1886, –the anniversary of the Battle of Antietam–to honor the 4,000 Hartford citizens who served in the Civil War, and the 400 who died for the Union.
The Arch
This monument is made of brownstone from Portland, Connecticut, and cost about $60,000 (from the city treasury) to build. Notice especially the terra cotta frieze depicting scenes from the Civil War, and midway below it, eight-foot-tall statues representing the various kinds of residents who left their homes, families and businesses to fight in the War: student, farmer, freed slave, stone mason, carpenter and blacksmith. The original terra cotta angels (Gabriel and Raphael) crown each tower, were replicated in bronze and replaced in 1987 as part of a restoration.
Activities
- Look at the arch and send answers to the following questions. (a) What is the color of the brownstone in the Arch and what materials do you think make up the hue? (b) Look at the grain of the stones and identify if it is round or angular. Why do you think this is the case? (c) Feel the rocks. Explain the texture and your views on how durable this rock would befor building large structures
- Upload a picture of you with your GPS in front of the arch (optional)