I am remodeling my kitchen and putting in a new cooktop. My house was built in the early 70's and the cooktop was original. The wire coming in from the wall has red, black, and bare (not copper). The new cooktop has red, black, and green. I was doing good I thought and was going to install new junction box and wire red to red, black to black, and green to bare. But after searching the net I am afraid since my bare wire coming into the wall isn't a ground since it isn't copper. My old cooktop had red, white, and black wires. The white wire was wired to the bare wire but was also attached to a short white wire attached to a nut in the junction box I assume for a ground. Not sure what to do next, not sure if red/red, black/black, and green/bare is correct. Can anyone help?