There is a strange thing I am experiencing with acrylic paint.
Early in the day on Wednesday September 22 I brushed a glaze of gloss medium and phthalocyanine blue onto an old canvas, and also did some collage with a different bottle of gloss medium.
That afternoon I was using Liquitex chromium oxide green that I had earlier transferred to a jar, and thinned with medium and a bit of local spring water (w/ iron and who knows what else!). The paint in the jar was creamy consistency, but when I put my wet brush in it, the paint on the brush came away clotted, like miniature cottage cheese curds.
I put that aside, put a bit of fresh tube chrome green in a clean dish, and used a clean brush with distilled water- the same thing. I tried a clean, dry brush, other paints, other brands, so far, everything immediately turns to clots.
I am trying to paint without brushes –or painting the clumps out with a stiff brush, as in painting on bare wood which I did last night. In the case of the gold paint suddenly skinning over – no. After a few minutes exposed to air, mixing turned it to a strange solid mass without any sticking power.
So far Palette knives seem ok.
So, What? Extreme heat this summer? dehydration? sunspots? ash from the fires? redwood pollen? Three outer planets retrograde in Capricorn . . ? activated the polymers and caused them to clump, and/or quickly skinning over.
I had seen a similar reaction once when I accidentally put rubbing alcohol in paint. I have a lot of (mostly) old paint, never had this happen before, except thickening through evaporation, often resolved by thinning w/ medium. Old paint just dries up.
I had used windex on a sheet of glass nearby last week, and am feeling some kind of residue on my hands today. So, cleaning all brushes, palettes, rags, glass working surface with clean water.
Meanwhile, cottage cheese might be a fine texture/technique, worth playing with, until I get this sorted, and/or, go shopping.