Mining got off to a slow start, taking place only sporadically from 1861-86 but then mining activity became more or less continuous from 1886-1915. The area was then quiet for 15 years until it started up again in the 1930s. #nspoli#cbpoli@Pier12Hugh@BernJordanMP#NovaScotia
A 25-ton ball mill was installed in 1935 but operations were discontinued due to unsatisfactory returns from the milling – too much #gold was being lost to the tailings instead of being recovered. #nspoli#cbpoli@Pier12Hugh@BernJordanMP#NovaScotia
The mill equipment was designed to process ore from one part of the mine but was not as effective with ore from another part of it. Attempts to improve the milling didn’t work and the mine shut down. #nspoli#cbpoli@Pier12Hugh@BernJordanMP#NovaScotia
In 1937 the Lacey Mine was taken over by @NS_Energy_Mines and a second 25-ton ball mill was installed. The mine was operated under the Mine Apprentice Project, a gov program that trained about 500 men (yes, they were all men!) in “modern” hard rock mining techniques from 1937-40.
The outbreak of World War II brought the program to an end – educating miners was a lower priority as the nation prepared to fight the war. (Somewhat ironically, Canadian miners played important and unique roles in the war. #nspoli#cbpoli@Pier12Hugh@BernJordanMP#NovaScotia
For example, they dug many kilometres of tunnels into the Rock of Gibraltar to protect Allied soldiers from bombardment. The tunnels could hold 16,000 soldiers and everything they needed for 16 months. #nspoli#cbpoli@Pier12Hugh@BernJordanMP#NovaScotia
The Rock of Gibraltar was strategically important because it let the Allies control access to the Mediterranean Sea. Canada’s experience with hard rock mining was key to holding it.)
The transition to ball mills was an important one. #nspoli#cbpoli@Pier12Hugh@BernJordanMP
Most #NovaScotia gold is in quartz veins, which means the #gold needs to be separated from the quartz and other host rock. The first step is to pulverize the rock/ore so the gold can be chemically separated from it. #nspoli#cbpoli@Pier12Hugh@BernJordanMP
The most common technology in #NovaScotia for pulverizing ore in the second half of the 1800s and early decades of the 1900s was the stamp mill – a large machine that crushed #gold-bearing rock by stamping it over and over. #nspoli#cbpoli@Pier12Hugh@BernJordanMP#NovaScotia
In a stamp mill, quartz was washed with water and moved under the stamps that went up and down, crushing the quartz into sand. Each stamp would weigh about 800 to 1,000 pounds and repeatedly struck the ore.
In the 1800s, mercury was then used to separate the #gold from the sand.
#Gold dissolves in mercury but mercury does not absorb other impurities so it was effective at separating the gold from the pulverized host rock. The mercury/gold mixture was recollected and heated until the mercury boiled away. #nspoli#cbpoli@Pier12Hugh@BernJordanMP
A simple still like those used to make alcohol would draw away the vaporized mercury, collecting it for reuse, leaving mostly pure #gold. The gold was then refined for greater purity and formed into bricks or nuggets. #nspoli#cbpoli@Pier12Hugh@BernJordanMP#NovaScotia
Mercury hasn’t been used in #NovaScotia#gold mines since the early 1900s because it is bad for the environment. (Misconceptions about modern gold mining stem from historical mining practices, like the use of mercury, that we agree were not good enough. #nspoli#cbpoli
Ball mills eventually replaced stamp mills. A ball mill has a cylindrical shell that turns constantly. The ore and heavy, steel balls are placed inside it. As the shell turns, the balls pulverize the ore. #nspoli#cbpoli@Pier12Hugh@BernJordanMP#NovaScotia
This facilitates the formation of placer (aka alluvial) deposits - #gold that erodes from bedrock deposits and becomes concentrated in rivers and shorelines by water. #nspoli#cbpoli@Pier12Hugh@BernJordanMP#NovaScotia
In other words, #GoldRiver erodes some of the rock that hosts the gold and carries it downriver until the #gold settles out.
Panning for gold means scooping up water, sand and gravel in a pan and swirling it around. #nspoli#cbpoli@Pier12Hugh@BernJordanMP#NovaScotia
The #gold, which is very heavy, settles on the bottom of the pan while the lighter gravel and sand washes over the side. While it was not used extensively at #GoldRiver, panning was a simple but effective small-scale method of extracting gold at many historical sites. #nspoli
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For example, an e-car has 183 pounds of copper wiring in it because copper is used in every major component from the motor to the inverter and the electrical wiring. There is about four times more copper in an e-car than in a car with an internal combustion engine.
There are about 400 electric cars on Nova Scotia roads - a total of over 73,000 pounds of copper!
An electric car uses 25-50 grams of silver, so Nova Scotia’s 400 e-cars contain about 15,000 grams of it.
Concrete is a mixture of aggregates and paste. The aggregates are sand and gravel or crushed stone; the paste is water and portland cement. (The terms cement and concrete are often used interchangeably, but cement is actually an ingredient of concrete... #nspoli
...Cement is the glue that holds concrete together.)
Reinforced concrete means the concrete is poured over a frame, usually steel bars, that give the structure greater strength. #nspoli
The short answer is yes, sinkholes are real but no, they are not a major risk and should not prevent you from enjoying outdoor activities.
Most natural sinkholes are caused by groundwater naturally eroding rocks like gypsum, salt and limestone which are water-soluble. #nspoli
The water erodes the rock, leaving an underground cavern. Eventually, the weight of the rock and earth above the cavern causes the sinkhole to form. Sinkholes can form either gradually (i.e. a small depression appears and perhaps grows larger over time) or by sudden collapse.
The New Campbellton coal mine was opened in 1862 by Charles J. Campbell, a former Member of Parliament, Member of the Legislative Assembly and executive council member. The community had been named Kelly’s Cove but was changed to New Campbellton in 1862 in honour of Mr. Campbell.
A sample of New Campbellton’s coal was sent to the 1865 Dublin Exhibition and “was very favorably noticed by the Judges,” according to a report. #nspoli#cbpoli#novascotia#capebreton#nshistory
Mining built #NovaScotia! #Halifax was founded in 1749 and its first court house is reported to have been built by 1754 on the northeastern corner of Buckingham + Argyle streets. After the building burned in 1789, the courts were temporarily housed in various buildings. #nspoli
In April 1851 a bill to provide Halifax with a county court house was passed. Mr. H.G. Hill, a prominent #Halifax architect, prepared a plan for a wooden building.
However, since the records of the county, wills, deeds and other papers of public office were... #nspoli#novascotia
...to be stored in the court house, it was important that the building be fire-proof. Also, a number of serious fires in #Halifax in 1857 led to the passage of a bylaw that required large buildings be made of stone or brick, so Hill's plans for a wooden building were abandoned.
The Sullivan Creek #coal mine, before and after!
It's one of several mines reclaimed around #AlderPoint#CapeBreton in the late 1900s/early 2000s - examples of how mining makes temporary use of land and then land can be used other ways. #nspoli#cbpoli#novascotia@JaimeBattiste
The first mine in the area was the Scotia Mine, or #NovaScotia Steel & Coal Company No. 4 Colliery, on Toronto Road, which operated on the Sydney Main (Harbour) Seam from 1915 to 1921. #nspoli#cbpoli#novascotia@JaimeBattiste
Coal quality and structural issues (including water inflow) plague the Harbour Seam west of Florence so upon closure of the colliery, production on the Harbour Seam was limited to the Company’s No. 3 Colliery in Florence, which had opened in 1902... #nspoli#cbpoli#novascotia