Um... well, It depends how often you have them. It's probably just because you're on your heavier days, But if it continues, you should probably see a physician. Black blood is dead blood and fresh blood meanings you are bleeding. Sometimes near the end of your period you can get some stringy, black blood. This blood is old and nothing to worry about, but it's always wise to get your yearly physical.
blackish grayish
its blackish brown
yes
Pinkish Blackish kinda
some clouds are this grey blackish color because they are full of rain. if you see these in the sky when you playing with your friends it means that it is about to rain
they are blacky brown
well..its hard to tell what colour it is, but its definitly red, or a bit blackish red.
It reacts with sulphur present in the atmsphere and forms silver sulphide which is black in colour
Most octopus secreted blackish ink that is mostly made up of black pigment melanin.
Bile which is used to break down food in the stomach is dark yellow to blackish brown in colour. It is this which colours the excretia.
It can differ from deep brown with silver-gray speckles, but it can rand from yellowish or grayish brown to almost black
red, like a spanish NT's official colour:)