What is the colour of ferric oxide?

Hint: We know that in nature all metals are not going to be available in their pure form. Most of the metals are going to be available in the form of their oxide derivatives due to the high reactivity of the metals towards the oxygen.

Complete answer:
As we know that the ferric compound or Iron \[\left( III \right)\] compound with formula \[F{{e}_{2}}{{O}_{3}}\]may be a widespread oxide of iron. The opposite vital iron compounds embrace metal or iron \[\left( II \right)\] oxide \[\left( FeO \right)\] and iron \[\left( II,III \right)\]compound with formula \[F{{e}_{3}}{{O}_{4}}.\] In any case, we are going to largely discuss oxide and its color here. Ferric oxide is found in nature because of the mineral iron ore. \[F{{e}_{2}}{{O}_{3}}\] may be an auburn powder. Therefore we are able to say, oxide encompasses a red-brown color. The red color is additionally generally referred to as brown. Meanwhile, if we have a tendency to think about an iron ore single crystal or the powder, the blue and inexperienced spectral ranges of the incident light-weight get absorbed severally. So, the most reason for the red color impression is that the unabsorbed proportion of actinic radiation \[~\left( 600-720\text{ }nm \right).\]
Ferric oxide red is employed as a coloring agent within the pharmaceutical trade for tablets and capsules. It’s conjointly an authority approved substance for cosmetic use wherever the finely small-grained red kind, which is commonly cited as jewelers rouge, is employed for sharpening numerous precious metals and even diamonds. Oxide is more used extensively within the iron and steel industries. It’s the first supply of iron. Iron oxides, in general, have completely different pigments starting from red and brown, black and yellow.
\[FeO\] is called iron oxide. In iron oxide \[(FeO)\] iron has an oxidation state of \[+2.\] So, we can write \[FeO\] as Iron \[\left( II \right)\] oxide. Iron oxide is an inorganic compound. We know that iron oxide is going to be available in nature in the form of Wustite. The color which is exhibited by the iron oxide \[(FeO)\] is black color. Iron oxide at room temperature is going to exist in powder form.

Note:
Remember that however, compared to the one crystal, we've to think about the absorption and scattering properties to clarify the red pigments of the oxide powder. Once we leave the pigment powders, the part of the light-weighs the sunshine.