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.
Slavery did not supply the labor force in the northern colonies, but there were slaves in the North. By the 1740s, Philadelphia was 9 percent slave; New York 18 percent. In total, there were more than 15,000 slaves in New England. There were obvious differences between slavery in the North and South.