BlueClue is a quick and dependable field test for the detection of nitrates found in gunpowder. Upon firing a weapon, gunpowder is blown back in the direction of the shooter. These deposited particles may be collected using the included adhesive lifters. After collection, the lifter is returned to the test and the glass ampule is broken. After several seconds of exposure to the liquid chemical small blue specks will appear to indicate the presumptive presense of gunpowder particles. Provided as a package of 10 tests.