What is the value of 1972 penny heads on both sides d mint mark?

This is a "magic" coin - a coin made for magicians made by taking two pennies, splitting them each in half, and putting the two "heads" sides together. You should see a seam around the edge where the two halves are joined. If it's made very well, the seam will actually be on one of the faces, right at the rim.

Its value likely depends on the skill with which it was made - probably $2 - $5 or so.