On my short nails, this deep brown with a warm shimmer did look like coffee beans. It was a fun color to mix, but not a color I’d wear every day. The photos make it look redder than it actually was, though.
You can make brown by mixing orange and green, but I used a cheapo brown creme. I added orange shimmer drop by drop and mixed it. From there, I added some gold shimmer- try to use an intense one, but make sure the shimmer is very fine. A gritty shimmer will just make clumpy nail polish. Invest in some thin gold shimmer that’s sheer on the nail by itself- it will be very useful to make dark colors really stand out. You could also mix the brown base with a shimmery red to get a beautiful fall burgundy. Just don’t mix the brown with a cool color like silver or light blue, unless you want a sort of washed-up beigey color. It could be cool in a grungy way maybe but I can’t get it to look like anything other than a mistake.