Atlantic Slag Company

The Atlantic Slag Company sold an unusual product. Well, it’s right there in the name: slag.

Nova Scotia had a long history of steelmaking, starting in the 1870s when Canada’s first steel was produced in Londonderry, Colchester County (

Steel is mainly iron and carbon, and the carbon is derived from metallurgical coal, which contains more carbon, less ash and less moisture than thermal coal, the kind that generates almost half of Nova Scotia’s electricity. Nova Scotia’s world class coal deposits provided the coal for steelmaking, and various mines and quarries provided other essential materials, including iron ( and limestone, which is used as flux in the smelting process to promote fluidity and remove impurities in the form of slag (

By the 1950s, Nova Scotia had large quantities of slag at places like Londonderry, Ferrona, Sydney and Sydney Mines. Slag occurs as a molten liquid melt and is a complex solution of silicates and oxides that solidifies as it cools. Each slag deposit is unique to the plant in which it is generated but most slag is nontoxic and safe from a health and environmental perspective.

Slag has many uses, including in cement, as aggregate in construction and as fertilizer. Several Nova Scotia government memos written during the 1950s and 1960s discussed potential uses for Nova Scotia’s slag, viewing it as a resource and wanting to find ways to take advantage of the material.

It was against this backdrop that the Atlantic Slag Company started operating in the early 1950s. Halifax businessman Sydney J. Simon bought sites in Londonderry and Ferrona (Eureka, Pictou County, now) where steel had been produced decades earlier, planning to sell their slag for various purposes, discussed in the advertisement below.

An article in Department of Mines files, believed to have been written around 1954 but by whom is not indicated, said Simon bought 12 million tons of slag at the two sites. A 1961 Department of Mines memo later suggested that estimate “may be questioned as possibly being excessive, but there is no doubt that a considerable tonnage is available.”

The memo pointed out that the Atlantic Slag Company was not the first to try to make use of the slag: “The Elmac Company Ltd. of Amherst for some years obtained slag for use in its rock wool insulation plant from the Londonderry deposit and considerable amounts have been used on highways and for use in private driveways.”

The 1961 memo also said, “The Atlantic Slag Company appears to be non-existent at present and apparently its past years of operations were not successful in disposing of any appreciable amount of the slag.”

However, the company was active in 1962 when Simon announced that Pugwash Crushed Stone Ltd. had agreed to buy at least 9000 tons of slag over three years for use in construction. Pugwash Crushed Stone had an option to extend the contract another five years, according to a media report about the announcement. The article also noted that “C. and U. Belliveau of Shediac” was hauling slag across the Nova Scotia-New Brunswick border for use in manufacturing building blocks. (C & U Belliveau Concrete Products Ltd. was founded in 1960 and is still active today.)

Simon also announced that the Atlantic Slag Company was donating 1000 tons of slag to the community of Londonderry, to be used under the direction of Mrs. Katherine Purdy for maintenance of cemeteries.

The 1962 article suggested there were about 2 million tons of slag in Londonderry, far less than what would have been required to make the earlier 12 million tons estimate plausible. Londonderry produced steel for decades and Ferrona only produced it for a few years, so the majority of the 12 million estimate would have had to come from Londonderry.

A 1962 Department of Mines memo, commenting on the Pugwash Crushed Stone announcement, said “the [Londonderry] dumps extend eastwards from the Rockland River and at the river bank, where a site has been cleared, have a height of some 80’. A small crushing and screening plant is set up on the cleared site and has been worked intermittently by Mr. Russell Blair to supply ¼”- ½” material to C and U Belliveau of Shediac. Slag material has been dozed or shovelled from the top of the dump down wooden chutes to the crushing site.”

The memo described a challenge the Atlantic Slag Company faced: “Because of variable iron ore in the blast furnace charge (due to mixing of Londonderry and Torbrook iron and the use of ankerite) the deposit of slag at Londonderry is not uniform in quality.” This was a reference to the fact that in the 1890s, as Londonderry’s iron deposits were gradually depleted, iron ore from the Nictaux-Torbrook area was mixed with ore from Londonderry to stretch the Londonderry supply. Unfortunately, the blending didn’t work. Nictaux-Torbrook’s ore contained high levels of phosphorous and sulphur, which are impurities in steelmaking, and they lowered the quality of the Londonderry ore.

Still discussing the inconsistent character of Londonderry’s slag, the 1962 memo said, “Some beds are dense and very hard, requiring explosives to break them up. Other beds are relatively soft and friable, able to be broken up by pickaxe. These different beds of slag alternate through the deposit. The Ferrona slag is more uniform but very little information is available on it at present. It is not nearly as extensive as at Londonderry.”

The 1962 announcement may have been the Atlantic Slag Company’s high point since we could find no other references to the company in Department of Mines files after that year.

According to the Department, Simon had moved to Florida by the early 1960s but he visited Nova Scotia once every year or two. His sister continued to live on Beech St. in Halifax, so he still had a family connection to the province.

Discussing other potential uses for the slag, a 1958 government memo explained that the Dominion and Iron and Steel Company, which owned the Sydney steel mill, had been researching on and off since 1941 the possibility of using slag as agricultural fertilizer. While slag contains minerals that are impurities in the steelmaking process, those minerals can be used for other purposes such as improving soil quality.

In the end, the Dominion and Iron and Steel Company concluded that slag fertilizer was too bulky – and, presumably, therefore too expensive to ship - compared to competing products. There was not enough profit margin to make producing slag fertilizer worthwhile. The memo also mentioned that the “American Rolling Corp.,” a steel company, had produced slag fertilizer but discontinued production “after a disastrous explosion in their plant killed several men….”

A 1955 memo discussed the possibility of recovering manganese from the Sydney steel mill’s slag: “A suite of samples, both metal and slag, were obtained from one heat of steel at Sydney during the summer of 1954. Unfortunately, chemical analyses showed that the manganese content of these various samples was so low that it precluded any further investigation of manganese in this material.”

Canada’s first manufacturer of slag cement, which used slag from the Sydney steel mill as an ingredient, was founded in Sydney in 1905. See the story at

See the amazing story of steelmaking in Trenton at