Our April Meeting Fluorescent Minerals With Jeffrey Shallit
We are pleased to announce that our April Meeting will be all about fluorescent mineral. Originally the meeting was scheduled for February but had to be postponed because of inclement weather. The April 4th meeting promises to be both exciting and colourful. Jeff Shallit, from the Kitchener-Waterloo club, will be discussing the properties of fluorescent minerals. Jeff will bring samples to the meeting that will illustrate how certain 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.
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.
The April meeting will take place on April 4th, at the Knox United Church Meeting Hall beginning at 8:00 pm
Directions to our Meetings
Where:Knox United Church Hall
- 2569 Midland Avenue
Toronto (Scarborough) M1S 1R3
north-east corner of Midland and Sheppard Avenue
- We meet in the Church Hall which is the building north of KnoxUnitedChurch.
- To get to the Hall: When driving north on Midland just past Sheppard, you will pass the church which is on the corner. Then keep you eye out for a small laneway that runs south of the Hall. This leads to the parking lot behind (east) of the Hall.
If you miss the laneway, keep going till you hit a small street on your right (east) called Rural Ave.Turn right (east) and look for a driveway into the Church Hall parking lot. - The door to the Hall is visible from the parking lot. The door is propped open for the meetings. Come in the door & walk up a half a flight of stair into the hall.
- Meetings are help on the First Wednesday of the monthWhen: First Wednesday of each Month (except for July, August )
8:00 pm to about 10:00 pm- Although the meeting starts at 8 pm, try to get there earlier – the before meeting time is often just as much fun as the meeting. Come as early as 7:30 pmbecause there is always something going on.
- Before the meeting you can:
- chat with other members & guest speakers
- look at the Silent Auction Items displayed by members
- see the special guest speaker displays
- borrow a club library book from the cabinet
- sign up for workshops, classes or other volunteer opportunities at the side table
- help set up the chairs & pitch in with any other administrivia that people need a hand with
For information on our meetings email us