Art Video of the Week - Lightfastness & Fugitive Colours

I missed last week while I was on vacation, in Kentucky, to see the total solar eclipse. However, I'm back, and this week I wanted to touch on the subject of lightfastness and fugitive colours as I have been, recently, building a watercolour swatchbook for all of the brands I have that shows name, pigment (when available), lightfastness, and opacity.