Vaseline glassware will glow bright green under the black light because of uranium oxide in the glass, Cut glass will glow yellow; reproductions have no reaction or show a blue-white. Pattern glass made before 1925-30 fluoresce yellow; reproductions generally do not have any fluorescence.

Fabrics, WWII patches, uniforms and quilts: Most threads made before 1945-50 are natural fibers such as cotton, silk, etc which generally do not fluoresce. Synthetic fibers- rayon, polyester, etc. made since WW2 all fluoresce. This allows you to detect new military uniforms, new quilts, new doll clothes, etc. Even if old fabric is used to repair an old quilt, the new thread will fluoresce. The black light helps in detecting reproduced military uniforms, patches and etc. Now I would like to tell you direct; I know nothing about German patches, decals or uniforms. I've been told that these black lights help check to see if German Military patches and uniforms are real or repaired in anyway. I do know they work on American military patches and uniforms.

You found that old metal toy that looks almost new. Did you know that modern paint will fluoresce or glow under a black light, older paints will not, you can use this to determine whether a painted object is an antique or a newer reproduction in addition to determine whether each has been "touched up" and if so, how extensive was the repair.

Perhaps your son, daughter, grandsons, granddaughters, or you are into rock and mineral collecting. Whether your collection contains rare rocks or minerals, you have collected while traveling the world or items you simply find pleasing in color and shape, using black light can enhance your collection's display. Rocks and minerals adsorb the UV light and re-emit light of different color (red, white, green or blue). This is called Fluorescence and many rocks and minerals exhibit these attribute. An example of a long wave specimen is wernerite it's a bright golden yellow color under long wave.

Black lights are also used in finding those pet odors problem in your home, they are probably hidden in places you cannot see. These lights can find automotive air conditioners, coolant leaks. Do you leave in an area where scorpions are a problem? Under a black light, the scorpion is a bright green. It is interesting to note that a deep red light, which is on the other side of the visible range from ultraviolet is employed when catching night crawlers at night.

They are also used in crime scenes to uncover body fluid*, finding counterfeit money, ID and document verification, Club hand stamp screening. There are probably a few 100 more uses for a black light.