THE EMPLOYEE INJURED HIS THUMB WHEN HE WAS TRYING TO REMOVE DRILL CORE FROM A SECTION OF DRILL TUBE. HE TRIED TO FREE THE CORE FROM THE TUBE BY HOLDING THE TUBE WITH ONE HAND AND STRIKING IT USING A WOODEN MALLET. AS HE WAS STRIKING THE TUBE HE INADVERTENTLY STRUCK HIS THUMB WITH THE WOODEN MALLET.