Preheat the broiler. Line a heavy baking sheet with coarse salt.
Bring the wine to a boil over high heat in a 5-quart saucepan. Add the mussels and cover the pan. Steam until the mussels have opened, 2 to 4 minutes. Discard any unopened mussels.
Remove the cooked mussels from their shells, reserving 24 half-shells. Arrange the half-shells in a single layer on top of the salt. Place one cooked mussel in each shell.
In a small bowl, toss together the breadcrumbs, oil, oregano, mint, parsley, salt and pepper. Top the mussels with the breadcrumb mixture and drizzle with extra olive oil. Broil until the breading is golden, 2 to 3 minutes.