Spiders can be any color!
Spiders produce waste material called frass, which is typically dark in color and can range from brown to black. As for urine, spiders release it in the form of uric acid, which is usually colorless or slightly yellowish.
brown
fluorite is varios colors sometimes colorless!
yes
No, lands in Magic: The Gathering are not colorless. They can produce mana of different colors to cast spells.
Spiders have circulatory systems just as humans do. However, their blood is colorless blood and is called hemolymph. It transports nutrients, hormones, oxygen and cells.
Red, Blue, Yellow, Green or colorless
There is no easy way to answer this question. The colors of spiders can change at each time they molt and get a new skin. The colors of baby spiders are not connected in any direct way to the colors of adults. So knowing the color of adults of some species is not a sure well to anticipate the colors of pre=adult members of their species. On top of that there are thousands of species of spiders, and it would be a long job to try to track down which spiders were red at which stage(s) before they reached maturity.
you can identify the poisonous ones because they look a little more exotic than regular spiders, like they have markings on them or have different combinations of bright colors on them. regular spiders are just plain black, brown or dark colors.
spiders can be any color some spiders are blended with other colors, some might have a design on their back
Sunlight appears colorless to the human eye, but it is actually made up of all the colors of the spectrum. This is why when sunlight passes through a prism or rain droplets, it gets refracted and we see different colors.