Colours are adjectives (and sometimes can be used as nouns).

 

The main colours in Italian are:

 

- Nero (and all its forms) / black

- Bianco (and all its forms) / white

- Grigio (and all its forms) / grey

- Azzurro (and all its forms) / light blue

- Giallo (and all its forms) / yellow

- Rosso (and all its forms) / red

- Arancione (and all its forms) / orange

- Verde (and all its forms) / green

- Marrone (and all its forms) / brown

- Rosa / pink

- Viola / purple

- Blu / blue

 

The adjectives describing colours agree with the noun they refer to except for rosa, viola and blue which are invariable

 

Examples:

 

Il mio cappotto è rosso, mentre la tua sciarpa è nera / My coat is red while your scarf is black

—> Rosso and Nero agree with the noun —> rosso (masc. sing.) , nera (fem. sing.)

 

Le mie scarpe sono blu, e il tuo cappello è blu / My shoes are blue and your hat is blue

—> Blu is invariable. It stays the same whether it refers to scarpe (fem. plur.) or cappello (masc. sing.)

 

Remember that arancione, verde and marrone are not invariable. They belong to the second class of adjectives (that in the singular form end in -e) therefore they have only one ending for the singular form (-e), and one for the plural (-i)

 

Examples:

 

Il mio cappotto è arancione, mentre la tua sciarpa è verde / My coat is orange while your scarf is green

 

I nostri cappotti sono arancioni, mentre le vostre sciarpe sono verdi / Our coats are orange while your scarves are green

 

Note that all the adjectives describing colours become invariable when used as nouns.

 

For example:

 

I miei guanti sono di un bel rosso / My gloves are of a nice shade of red

 

Guanti is plural but rosso is used as a noun here, and therefore it is in the masculine singular form.