Hex #309090 or rgb(48,144,144) in RGB space is the tint of cyan. It has hue angle of 180.00 degrees, value = 56 and saturation = 67. #309090 can be obtained by mixing 4 colors: 3 drops of magenta, 3 drops of blue, 5 drops of cyan, 5 drops of green.
Nearest safe hex - #339999. Below you can see the block with #309090 color and its structure: in procentage ratio and in drops of pigments. Click "TRY" button to move #309090 to the mixer and play with it.