Brownstones in Harlem (and elsewhere in the city) were all faced with the same brown sandstone originating from one main quarry in Portland, Conn.

After being mined on and off for centuries, the Portland Brownstone Quarries, has been closed for decades. Preservationists who want to achieve the look and feel of a New York City brownstone now have to turn to brownstone (dust) cement.

The loss of actual brownstone blocks is not necessarily tragic. That's because the performance of the stone, the object of so many New Yorkers' obsessions, is considered mediocre.

Edith Wharton also is said to have called it:

Today, most of the city's ''brownstone'' facades have been replaced with brown cement-based masonry.

Brownstone began appearing in New York City buildings in a significant way during the first half of the 19th century, and it quickly became the stone of choice for row house developers. (Brownstones are actually brick houses built with a stone facing.) Stone from Portland's quarries came out of the ground near the Connecticut River, so it was easy to get it to New York City -- as well as to other cities up and down the East Coast -- and was relatively soft, which made it easy to carve.

Unfortunately, that softness, along with cost-cutting by developers and the extremes of New York City's weather, made the stone liable to crumble, crack,

and flake.

The stone fell out of fashion, and by the 1940s, the Portland quarries, flooded by the Connecticut River in a major storm, were shuttered.

Brownstone, which is really just a brown sandstone, is still quarried in a few spots around the world -- including Britain, China and Utah -- but stone fabricators and materials experts say that there is really nothing quite like the stone that comes from Portland.

No matter where it's from, however, brownstone is no longer cheap. Portland Stone is said to be two or three times the price of Indiana limestone, the ''vanilla ice cream'' of stone, so cast stone (generally cement based) or stucco substitutions (cement again) are common alternatives.

Harlem From the Air

On the back of this photo (on sale at Ebay) the Triborough Bridge is noted to have cost $13,000,000.

Zooming into Harlem:

You can see the 125th Street Triborough Bridge, the 2nd Avenue, and 3rd Avenue Bridges, and Marcus Garvey Park in the far right and below as a ‘white’ barren, treeless rock. The Lee Building is the only large building - above the “er” in the word “River”, in the photo below:

The image is from 1938.