We all have them in our tool kit, but do we use them the way we should?
Article written for Gemworld International 2022. Category: Gem Testing
Author: Charles Evans FGA DGA
Written for industry specialists, this article challenges the conventional approach to the teaching of Colour Filters, which tends to view them as an entirely separate tool and learning concept. I suggest this could be improved and doing so would empower students with a deeper understanding of the filtering of light, and the wider influence of transitional elements, while also bettering the understanding of the graphic output of spectroscopic data, and the concepts of absorption and emission. Students often struggle to relate what they see through a colour filter with what they see in a graph.
If we view colour filters as having filtered certain wavelengths of light and encourage students to have a clear understanding of what wavelengths of the full visible spectrum have been removed and what this signifies, then a student will be better able to extrapolate results from any use and not just the traditionally proscribed uses. This widens the possible application of colour filters beyond the previously over-simplified and narrow area of usefulness that has marked their traditional usage and their current ‘disfavour’ as a gemmologists tool.
This article was published in Gemworld International, a vital and comprehensive resource to gemologists, jewellers, gem dealers and appraisers around the world. Take a look at the article online by clicking here. Or read the full PDF below.
