Sapphire (#0F52BA) is a dark, highly saturated blue hue. Sapphire is a jewel-tone blue named after the gemstone.
In RGB it is made of 15 red, 82 green and 186 blue. Its HSL hue angle is 216° with 85% saturation and 39% lightness, while its perceptual OKLCH lightness is 47% with a chroma of 0.176. For print, a starting CMYK mix is 92% cyan, 56% magenta, 0% yellow and 27% black.
As a text color on white, Sapphire has a contrast ratio of 7.15:1, which passes WCAG AA for normal text. On black it reaches 2.94:1 and fails AA. If you use Sapphire as a background, put white text on it. The APCA lightness contrast is Lc 20 for black text and Lc -89 for white text.
Its perceptual complement is #765300, close to coffee. Colors that look most similar are denim, cobalt blue, royal blue. It looks fairly similar to people with red-green color blindness (ΔE 1), so its meaning mostly survives.