Working as an interior designer, I select paint colors. I used to think whites were the hardest. There are a bazillion of them and they are ever so slight and each one is too blue or too yellow or too pink.
Then I thought grays were the hardest. Again, too blue, too purple to green. GRAY.
But then Husband and I decided we wanted black paint. In our house. We are not goth.
Found the perfect color, buy paint, too purple. Find the really perfect color, buy paint...and we have blueblack. The color is Iron Ore dammit and it looks so perfectly black on its little chip.
From now on, we will get the little samplers.
But for now, blacks are the hardest.