Breakdown of Это оригинальная картина, а не копия.
это
this / it is
не
not
а
and (contrastive)
картина
picture / painting
Questions & Answers about Это оригинальная картина, а не копия.
Why is it Это and not the feminine Эта to match картина?
Why do we use а here instead of но?
The conjunction а is used to show direct contrast or correction, which is exactly what is happening here (it is an original, as opposed to a copy). You use но when adding unexpected or limiting information, like 'It is a copy, but it is expensive'. For 'X, not Y' comparisons, always use а не.
Why is there a comma before а не?
Russian punctuation rules are very strict about conjunctions of contrast. You must always place a comma before а and но, even in short sentences where English might skip it.
Can I change the word order to say 'This is not a copy, but an original painting'?
Absolutely! You can flip the structure to Это не копия, а оригинальная картина. Both versions use the same conjunction а to contrast the two ideas, and both sound completely natural to native speakers.