Convoy C8 filtered UV flashlight, 365nm

Convoy C8 filtered UV flashlight, 365nm

The Convoy C8 is one of the best known longwave UV flashlights common to the market.

It uses either one or two 18650 batteries to produce a considerable amount of UV light. These torches come with an optional battery extender tube which helps to extend battery life.

Without the extension tube, the torch weighs 150 grams and measures 145x44.5MM approximately. With the extension tube the torch weighs 189.5 grams and measures 215x44.5MM approximately. With two 18650 batteries my torch weighs around 275 grams.

I do not supply these torches with batteries or chargers, to make it easier to ship these torches. 18650 batteries and chargers can be easily purchased online. 

Ultraviolet light is used in mineralogy and palaentology as a quick and easy test for material identification, and to find specimens made of certain materials while in the field. Corundum, Calcium, Chalcedony, Fluorite, and Sodalite are all reasonably common minerals that may demonstrate fluorescence under UV light. Fossils often glow too, due to Calcium minerals making up the main mass.

In antique hunting it is useful for similar reasons; identifying certain materials and especially in quickly verifying whether a clock is likely to have radium painted hands without the considerable expense of a quality geiger counter.

There are three types of UV light typically used in this context, which are, simply:

• Longwave UVA (365-400 nm)
• Midwave UVB (315-365 nm)
• Shortwave UVC (254-315 nm)

Different wavelengths can 'excite' different minerals differently - some pieces may light up under 255nm but not 365nm.

Now - Ultraviolet light can be dangerous. Prolonged exposure can cause sunburn, eye damage, and even skin cancer. I highly recommend purchasing a set of UV filtering glasses too.