Granulating yellows and reds are quite rare in watercolour. If you know of any, do let me know in the comments section. I'm trying to create a palette using only granulating colours and see how that would work out.
Some of the granulating reds I have are Daniel Smith Mayan Red (PR 287). My scanner wasn't able to capture vibrant reds that well but believe me when I say Mayan Red is really beautiful.
Daniel Smith listed Perylene Scarlet (PR 149) as a granulating red but it most certainly is not.
Potter's Pink granulates heavily but it's a rather muted colour.
Many of Kremer Pigment's paint are granulating so I wanted to test one, Irgazine Ruby (PR264). I'm not sure if I can call that granulating or uneven pigment separation (or maybe that's the same thing). Anyway, Irgazine Ruby does produce some interesting textures. The same pigment is used to make DS Pyrrol Crimson but we can see DS's version is more even and predictable.
These are the same mixes painted on Indigo Art Papers handmade cotton watercolour paper. The earlier ones were painted on Arches.