the incoming water is coming to my kitchen in a black plastic pipe. The stop valve on the pipe is broken. No worries since i can cut off the water supply from the valve outside. Anyway i would like to replace the indoor valve. The problem is that the water pipe is black plastic pipe and it must be very old since my house is 100 years old. I wonder what kind of pipe is it? Is it safe material and how can i do a joint in it? Similar way as with the new blue plastic pipes?