Learn Spanish (Latin America): Hace un año, el hierro local se exportó por primera vez. - A year ago, local iron was exported for the first time.

Both are grammatically correct, but the passive se (se exportó) is much more natural and common in everyday Spanish when the person doing the action isn't mentioned. You form it using se plus the third-person verb. Since el hierro (the iron) is singular, we use the singular preterite exportó.

Why is the verb in the preterite (exportó) rather than the imperfect (exportaba)?

The phrase por primera vez (for the first time) marks a specific, completed milestone in the past, rather than an ongoing background action. The time marker hace un año (a year ago) also points to a specific completed timeframe, which tells us to use the preterite.

Why do we use por in por primera vez instead of para?

Por primera vez is a fixed expression that always uses por. While por has many rules, the easiest way to handle this one is to just memorize por primera vez as a set chunk meaning 'for the first time.'

I know hace usually means 'makes' or 'does'. How does hace un año mean 'a year ago'?