Learn Russian: Это старинная шкатулка необычной красоты. - This is an antique jewelry box of unusual beauty.

This sentence uses the genitive of qualitative description, which is the focus of this lesson. Just like in English you can say a box 'of unusual beauty' rather than 'an unusually beautiful box', Russian uses an adjective and a noun in the genitive case to describe a deep, inherent characteristic of the object.

Could I just say необычно красивая шкатулка instead?

Yes, you could! Grammatically, необычно красивая шкатулка (an unusually beautiful box) is perfectly fine. However, using the genitive of description (шкатулка необычной красоты) elevates the register. It sounds more literary, poetic, and formal, which fits perfectly with the word старинная (antique).

Why does the sentence start with the neuter Это when шкатулка is feminine?

In this sentence, Это acts as a fixed demonstrative pronoun meaning 'This is', which introduces the subject. When stating 'This is an X', это never changes gender. You would only use the feminine Эта if 'this' were a modifier attached directly to the noun, as in Эта старинная шкатулка... (This antique box...).

Does шкатулка strictly mean 'jewelry box', or can it refer to any box?