How to Read Watercolor Paint Labels, Test Lightfastness, and Protect Your Art
Watercolor paint labels are tiny, confusing, and weirdly hard to understand if you don’t have a degree in physics or art. So if you’re crusing for some new art supplies on a Friday night after a glass (or something) let me break down how to best interpret all those extra details next to that flashy new color calling your name.
How to read a tube or pan
Look for:
Pigment code(s): e.g. PB29, PR101 - this lets you know what pigments are used to make that pretty color. Multiple pigment codes means it’s a blend, which isn’t bad, more something to keep in the back of your mind.
ASTM rating: I–V (if listed) - this will let you know how lightfast (or not) the paint as a whole is.
Series number: price tier (not quality - in my mind quality has more to do with the pigments than price, which don’t always corrolate, but I digress)
Most of these will be listed under the “more details” portion of the listing. Or if you’re in the store, you can use this handy app I’ve developed to look up that paint in your had right now.
How to test lightfastness at home
Want to get creative? Have some time on your hands? You can do this little science experiment at home.
Paint large swatches on watercolor paper - ideally acid free and 100% cotton.
Cut the paper in half
Store one half in a drawer
Tape the other in a sunny window- ideally south facing, but any sunny window will do.
Check after 1–3 months
The difference can be shocking—in a good, educational way. Post about it online (TT and IG @smrbrownestudio) and let me know how it turns out!
Storage and display tips
Have some art that you’ve painted? Gifted some watercolor artwork from a creative friend of yours? Besides sending an awesome thank you note, below is what you need to know about preserving those gorgeous colors:
Avoid direct sunlight - place the artwork on a wall that doesn’t recieve direct sunlight, and especially avoid south facing walls/windows
Use UV-protective glass - this should be designated on the frame when you buy it, can also be plexiglass which is safer if dropped etc.
Store originals flat, dry, and dark - not ready to frame yet? still deciding on a location? keep them out of the light until you’re ready. you could even rotate out your artwork. Could even add a fun seasonal dimension to echo any decor you have going on (i.e think vermont fall colors in October, and fun Capri paintings in the summer).
Safe pigments to trust
Rather than memorizing lists, I recommend using a reference tool while building your palette. I built this so you don’t have to memorize pigment and lightfast numbers. and it’s especially handy when you’re coparing brands and shopping online