D'oro vs. dorato
The Italian words 'd'oro' and 'dorato' both relate to the concept of 'golden', but they have distinct uses and connotations in the Italian language.
D'oro
'D'oro' literally means 'of gold' or 'made of gold'. It refers to something that is actually made of gold or has the color of gold.
Ho comprato una collana d'oro per mia moglie.
(I bought a gold necklace for my wife.)
Il tramonto ha dipinto il cielo di un colore d'oro.
(The sunset painted the sky a golden color.)
L'anello d'oro è un regalo di famiglia.
(The gold ring is a family heirloom.)
Dorato
'Dorato' means 'golden' in the sense of having a gold-like appearance or being gold-plated. It doesn't necessarily imply that something is made of actual gold.
La cornice dorata del quadro è molto elegante.
(The golden frame of the painting is very elegant.)
Il sole ha reso dorato il campo di grano.
(The sun made the wheat field look golden.)
Ho comprato delle posate dorate per le occasioni speciali.
(I bought gold-plated cutlery for special occasions.)
Summary
While 'd'oro' specifically refers to items made of gold or having the color of gold, 'dorato' is used for things that have a golden appearance or are gold-plated. 'D'oro' implies authentic gold, whereas 'dorato' suggests a gold-like quality or finish.