Non-renewable resources are resources for which there is a limited supply. The supply comes from the Earth itself and, as it typically takes millions of years to develop, is finite. Non-renewable resources can generally be separated into two main categories; fossil fuels and nuclear fuels.
But there were pockets of the North on the eve of the Revolution where slaves played key roles in the economic and social order: New York City and northern New Jersey, rural Pennsylvania, and the shipping towns of Connecticut and Rhode Island.
A large number of slaves who were born in Africa did not come directly to the English colonies or, later, the United States. Many people first spent some time on islands in the Caribbean before being brought here. Owners often purchased slaves from different parts of Africa.