Hand warmer

My wife & I work the outdoor interactive production of Bethlehem Story at Faith Chapel in Spring Valley. My wife works as a potter helping children making "pinch pots". Last year it was very cold for the night performances. Out fits have to be period so gloves & socks are not allowed. I have tried to make a sheep skin hand warmer for the back of her hands. If it gets cold and if it doesn't interfere with her making pinch pots she will test in 1st performance.