Our February Meeting Fluorescent Minerals

Our February Meeting Fluorescent Minerals With Jeffrey Shallit Our February 7 th meeting promises to be both exciting and colourful.  Jeff Shallit, from the K-W club, will be making a […]

Our February Meeting Fluorescent Minerals With Jeffrey Shallit

From the collection of Jerry Hemmingway. photo by Chris Robart

Jeffrey Shallit

Our February 7 th meeting promises to be both exciting and colourful.  Jeff Shallit, from the K-W club, will be making a presentation on the properties of fluorescent minerals.   Jeff will bring samples to the meeting and will illustrate how they react to ultraviolet light.   There will be at least one black light so bring any specimens you might have for possible identification. We may  even have a display for your viewing enjoyment.  Club member, Jerry Hemmingway, promises to bring something special.   Jerry is an advanced collector so expect something , nothing less than spectacular.

Here are some of the topics that Jeff will be discussing in detail:

  • Fluorescent minerals are those emit visible light when activated by ultraviolet (uv) light.
  • Ultraviolet light comes in different wave lengths; for example long wave, short wave and medium wave light may cause the same mineral to emit different colours.
  • Long wave uv light, black light, is the most common form of uv light found in sunlight.
  • Medium uv light is responsible for sunburn.
  • Short wave light has the most energy and is the most dangerous.  Fortunately for us, the ozone layer high above the earth blocks short wave uv light.
  • Phosphorescence: when a mineral continues to glow after the removal of uv light.
  • Thermoluminescence; when a mineral continues to glow after being heated.
  • Triboluminescence: crushed particles or the streak of a mineral that glows when activated by uv light.

 

About our Speaker

Jeffrey Shallit is a professor of computer science at the University of Waterloo, with degrees from Princeton and the University of California in Berkeley.   He specializes in fluorescent minerals and meteorites. Jeff is also bulletin editor  of the Kitchener-Waterloo  Gem and Mineral Club, and also the proprietor of Calaverite Fine Minerals.