South Manchester

Nova Scotia has two halves geologically: The northern half came from Europe and the southern half from Africa. The Cobequid-Chedabucto Fault System (CCFS) is where they collided 400 million years ago.

People sometimes think of it as a single fault that cuts the province in half. In fact, it's a fault zone or system, not a single fault. (It’s like a broken phone screen that has a spider web of cracks, not just one.)

The heat and pressure caused by two tectonic plates colliding and rubbing against each other for millions of years caused earthquakes and melted rocks in Earth’s crust. It also caused the concentration of many minerals. There are hundreds of known mineral deposits in the area, many of which were mined.

For example, there are many iron deposits along the CCFS that were mined in the 1800s and 1900s. The colliding tectonic plates opened up a series of faults (fractures) between the plates. The faults tapped into Earth’s mantle and allowed huge amounts of iron-rich solutions to escape and rise toward Earth’s surface. As these fluids got closer to the surface – away from the heat of Earth’s centre and the heat of the tectonic collision - they cooled and solidified, forming iron deposits.

One example is the South Manchester iron mine in Guysborough County. The deposit was discovered in 1881 by a Mr. Cumminger, who reportedly shipped 200 tons of ore to the iron smelter at Londonderry, where Nova Scotia’s most successful iron mines were located.

A 1919 report said the Manchester mine was first worked by an open cut hundreds of feet in length and fifteen feet deep, and that several thousand tons of ore were taken out and shipped abroad. However, an examination of the site in 1987 found no evidence of this significant excavation so it is not known whether the report is accurate.

Ore was extracted in 1895, but it was merely stockpiled. Five years later the Dominion Iron and Steel Company reported there were about 91 tons of "good" ore on the stockpile, but they did little actual prospecting at the site.

In 1913, John Mason & Associates of New Glasgow made some excavations.

In 1919, two shafts were sunk, one 24 metres deep and the other 9 metres deep. The deeper shaft revealed a vein nearly 1 metre thick at a depth of 9 metres. This vein then pinched (narrowed) to 46 centimetres at 12 metres. A geological investigation by the Manchester Iron Mine & Railway Company followed.

In 1931, John Mason returned and shipped the stockpiled ore to Sydney, Cape Breton, and extended the underground workings. An H. B. Gillis made a brief examination of the property for the Dominion Steel & Coal Company that same year.

In 1943 a brief examination was made by G. V. Douglas for the Nova Scotia Department of Mines. Some time later another investigation of the area was made by F. W. Didgon & Sons Limited, who did some chemical analyses on samples.

J.E. Dawe carried out prospecting in the area of South Manchester, including the old mine site, in 1954. Dawe discovered two new vein exposures of specular hematite, one near the north end of Hadley Cove about 1.6 kilometres west of South Manchester and the other near Moose Point, about 1.2 kilometres to the east of the mine. (Hematite is the most common rock from which iron is extracted.)

In total, only a few thousand tons of ore was produced from the mine.

The South Manchester mine was small but it’s worth noting because nearby a specular hematite vein is exposed on the beach at South Manchester. This is likely the best site in the province to see specular hematite (picture below). The site is easily accessible, not hard to locate and is on Crown Land. The vein is only exposed at low tide so plan accordingly if you decide to go.

This vein is likely part of the same fault zone that produced the South Manchester mine’s iron deposit. Many of the other iron mines along the CCFS may have similar hematite veins but they are either overgrown or not exposed as they are at this beach.