What’s the difference between Nickel Azo Yellow (PY150) and Rich Green Gold (PY129)?

Top: Mission Gold – Green Gold (PY150), a Nickel Azo Yellow.
Bottom: Daniel Smith – Rich Green Gold (PY129).

Both of these golds are metal complex azomethine yellows: PY150 made from nickel, and PY129 made from copper. Both are highly transparent, smooth, and dispersive. They differ in hue; Nickel Azo Yellow (PY150) is more of a yellow – warm and ochreish in masstone and cool and lemony in dilute – while Rich Green Gold (PY129) is more, well, green! It looks to me like pickle brine. Both make glowing yet subtle, naturalistic greens with Phthalo greens/blues.

They have the same role as green mixers, so which of these should I pick for my palette?

Color Mixes

For all of these mixes, I used Mission Gold’s Green Gold (PY150) and Daniel Smith’s Rich Green Gold (PY129). Despite the similar names, MI Green Gold is actually Nickel Azo Yellow.

Quinacridone Magenta (PR122)

When it comes to magenta, the difference is striking. PY150 makes intense golds and oranges, while PY129 makes more muted and brownish tones.

Phthalo Turquoise (PB16)

Both are absolutely lovely with PB16, making a range of glowing greens. The PY150 ones are cooler and cleaner, while the PY129 ones are warmer and more muted.

Phthalo Green Blue Shade (PG7)

Again, clean middle greens (similar to Hooker’s Green) from PY150. More muted, yellowy greens from PY129; these remind me more of Sap Green.

A scratch page of PY150 and PY129 green mixes.

Making My Choice

I initially mentally classified PY150 as a yellow and PY129 as a green, which made it easier to justify having both on my palette. But the more I’ve used PY129, the more I’ve realized it mixes more like a yellow than a green (it makes green with blue, and with yellow, it only makes a different yellow). I now find these two colors so similar as green mixers that it’s hard for me to justify having both on my palette. But I also like them both a lot, so it’s hard to choose.

As a green foliage mixer, both are great, and the mixes are so similar that it’s difficult for a camera to pick up the variation. It comes down to which “mood” of green you want: while both can mix a variety of bluer or yellower greens, PY150’s lean more toward a crisp Hooker’s Green while PY129’s lean more toward a muted Sap Green. The unmixed hue of PY150 is more yellowish, so it gives you more range on the yellow end, while the unmixed hue of PY129 looks more greenish, so it gives more naturalistic highlights to foliage.

Bigger differences come in mixes on other ends of the color spectrum. PY150 is more versatile; in addition to its great greens, it also mixes glowing, intense reds and oranges. (It is the key ingredient in many commercial mixes, including Quinacridone Gold hues; to me, it’s the quintessential “golden hour” gold.) Meanwhile, PY129’s greenish tones create more opposition to the warm reds, so it mixes much more muted, brownish shades. PY150 can be used as a primary yellow, but PY129 is better slotted as a green specialist.

I do find that in most cases, Nickel Azo Yellow is more useful. This is especially true in summer, where NAY mixes those clean summery greens and RGG can be too muted. However, in my January 2021 nature spots, I found RGG perfect for specific winter greens, like moss catching the sunlight. The more muted mixes feel appropriate in winter, where a green too bold would stick out. (For spring and fall, I’d yeet them both and use bolder middle yellows.)

Winner: Nickel Azo Yellow (PY150) generally, and especially for summer; but I love Rich Green Gold (PY129) for winter.