Modern mining creates jobs for Nova Scotians, provides essential materials we all use every day and takes excellent care of the environment.
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.
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...
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.
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. 
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.
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.
The person who asked isn’t the only one who has noticed the circles. With satellite images so easy to access on the Internet, others have also noticed them, including the excellent staff @NS_Energy_Mines.
Iron mining and smelting began in #NovaScotia in 1825 when iron mines opened at Nictaux Falls, #AnnapolisCounty, and the Annapolis Iron Mining Company built a blast furnace at Clementsport between #AnnapolisRoyal and #Digby.
The first land grants in #VictoriaMines were given to Irish settlers in 1794 and in New Victoria in 1808.
However, #GoldRiver is believed to have been named after a Mr. Gould, an early settler, and it’s original name was Gould River. The name was changed to Gold River before #gold was discovered there.
The bank was built because of the economic boom that occurred in #Sydney in that era. Large steel plants located in Sydney, fed by nearby #coal mines, made Sydney a hub of commercial and industrial activity.
It’s a great example of reclamation mining – cleaning up historical mines by completing extraction and returning them to nature or preparing them for other uses.
Mining/quarrying is #NovaScotia’s highest-paying resource industry. Its average total compensation (wages+benefits) is $87,000 per year. An entry-level job like haul truck driver pays an average $25/hour.
#NovaScotia has 2 halves geologically: The northern half came from Europe and the southern half from Africa. The Cobequid-Chedabucto Fault System is where they collided 400 million years ago. This caused earthquakes, melted rocks+concentration of minerals like #gold+zinc.
#SydneyMines was named after Thomas Townshend (1733-1800), First Viscount Sydney, who was British Home Secretary in the Pitt Government in the 1780s. He was an important player in negotiating the Canada-US border.
Gypsum quarrying began in #HantsCounty in the 1700s when farmers exported it as fertilizer. #Gypsum fixes alkaline (high pH) soil. US inventor Ben Franklin learned this from the French and brought the idea to the US in 1785.
Only the early Acadian mines at Joggins, which provided coal for Fort Beausejour and Port Royal, and the French mine at Port Morien, which provided coal for Louisbourg, are known to be older.
The cavities fill with silica-rich liquid that contains trace amounts of iron. Over time, this liquid forms crystals that line the cavity walls. After crystallization, gamma rays, emitted by radioactive materials in the host rock, irradiate the iron to produce the purple color. 
The historical quarry is on turn-of-the-century geological maps but there are no official records of its production, so precise dates aren’t available.
It was later quarried to produce rock fill and armour stone.
As a son of Jupiter, Vulcan was the creator of his father's lightning bolts. He also made armor, weapons and jewelry for the gods and heroes of Rome.