All MPC was paper money. During the monsoon I dug my wallet out one day. It was in my pack and wrapped up in plastic with about 900 rubber bands wrapped around it to keep the water out. When I looked in it the money had just dissolved. One side of it had a perfect impression of a $20 bill, but the bill was just gone. I didn't need to get in it very often because we were doing 30 days out and 5 days in. In the 30 days out we might not even see a building, a farm hootch, or nothing so you didn't need to be getting into you wallet too often. The 5 days in weren't much to brag about either. We spent the time at a place called the Rock Crusher (they crushed rock for roads in the area) between LZ Baldy and LZ Ross. The only place to spend any money was at a hootch some kid had set up just outside the lines. Booze, beer, and dope.
When we were at Hotel Battery they changed the money. They would do this every once in a while. And when they did the old money became worthless instantly. Anyway, at the intersection of the main road and the road to Hotel Battery an old woman had a whorehouse. We called her Lili, it may have actually been her name for all I know. She must have had a butt-load of MPC from years of selling girls to Marines. When her riches became worthless she shot herself.