what exactly is blacklight? What is its relevance to black velvet
paintings in the 1970's?

Hi there!

Black light is actually the "invisible" part of the light spectrum  -
ultraviolet light (all colors beyond violet).

There is a brief but nifty description of how black light works at
HowStuffWorks.com:

How Does A Black Light Work?
[ http://www.howstuffworks.com/question59.htm ]

Black light figured heavily in the psychedelic black velvet art of the
'60s and '70s because of its ability to make
flourescent/phosphorescent colors "glow in the dark".  Paintings and
posters of the era often featured art in phosphorescent/flourescent
paint on black vlevet - the black velvet creates a sharp contrast to
the glowing colors so that when these are viewed under black light,
the art appears to "pop" from the poster/painting.  When viewed under
black light in a dark room, they give the illusion of floating in
mid-air, independent of any background whatsoever.

For obvious reasons, these were very popular among the drug using
"counter-culture", but were often found in the collections of
"straight-edge" pop culture collectors as well.

This is what The TrippyStore [http://www.trippystore.com ] has to say
about black light:

"No lighting effect on Earth can quite compare to that of a black
light.  The UV light produced by black lights, though invisible to
human eyes, is absorbed by fluorescent colors and re-emitted in the
visible spectrum much brighter than a normal color.  The way ordinary
items glow under black light is amazing, while things like posters,
candles, or Lava lamps specifically designed for black light are
positively mind-bending.  Once you see your room under black light,
you'll undoubtedly want to see it again and again."

There are some terrific examples of modern black velvet/black light
art here:

Black Light Posters!
[ http://www.posters-art-prints.com/black-light-posters.shtml ]

...and a collection of "vintage" style blacklight art here:

The TrippyStore.com
[ http://www.trippystore.com/cgi-bin/shop/category/blacklightposters.html
]


If you're interested in more information on the origins of black
velvet art, Juxtapoz Magazine has an article in the January 1999
issue, which you can order here:

[ http://www.mpawson.demon.co.uk/jux.html ]

Hope this is what you're looking for!

Peace & Love, man,

missy-ga <--child of the '70s

Another feature of blacklights (which I'll bet Missy remembers as well
as I do!)is that blacklight causes polyester (and other manmade
fabrics) to fluoresce, that is glow. So when used to light dancefloors
black light resulted in rather ....ummm ... disconcerting exposure of
those of us wearing polyester underthings.

This feature of polyester and other modern fabrics allows blacklight
to be used to authenticate antiques.

http://www.antiqueresources.com/articles/blacklight.html

K~ <--- also of the 70's