Fluorite is a soft and brittle mineral that can occur in wide range of colours, ranging from bright green, blue, pink and purple to much paler shades of these colours to virtually colourless. Its hardness is 4 on Mohs' hardness scale and it has 4 directions of perfect cleavage, which makes fluorite unsuitable for most jewellery.

The Madoc area produced fluorite for industrial purposes between 1905 and 1961. Mineral collectors have occasionally unearthed fine mineral specimens since then. There are dozens of sites in the Madoc area where fluorite was either produced or known to occur. The gemstones offered for sale on this page have been cut from fluorite collected fairly recently from the Highway 7 area near Madoc.

FLUORITE from Highway 7, near Madoc, Ontario Sample on left shows the colour shortly after the fluorite was collected. Sample on right shows the colour after 2 years of exposure in a window sill.

The fluorite from Highway 7 possesses an interesting colour change effect. Its colour in sunlight or fluorescent light is mostly blue or blue-green and when viewed under incandescent light its colour is mostly purple. Unfortunately this colour change effect is not permanent. This effect fades upon exposure to light and after a period of time in the sun the colour changes to medium-light green. I did an experiment to test the stability of this colour. I started with two very similar pieces of fluorite. I place one piece on a window sill in my workshop and the other was kept in the dark. A month later the fluorite on my window sill changed to a medium-light green colour. I don't know how much time it takes for this change to take place but certainly less than a month. After 2 years in the sun the fluorite on the window sill was sill green, while the fluorite kept in the dark retained its blue violet colour. The included photo shows these two fluorites.

Please note that the colour of these gems was very difficult to accurately photograph, especially when it came to capturing the colour change.  I took photos of these gems under both fluorescent and incandescent light in an attempt to show this colour change.  The colours shown here might be a little different from what you might observe at home, but I've tried my best with a difficult subject.