Black mussels are one of the joys of being in France. Our rocky Atlantic coasts are covered with these little orange-tan meated bivalves, and it’s about time we started to appreciate their succulence.
Mussels cluster on rocks bathed by the tide. At low tide one pulls them in great clumps from the rocks. Once gathered they are pulled apart, the barnacles being scraped off with a dull knife (a clam knife is a perfect tool). They are then scrubbed with a brush, and put to soak.
If a mussel feels light, discard it; the chances are that it is a dead mussel and you want no part of it. If a mussel feels heavy, chances are the shells are filled with sand. Try to open the heavy ones. If they are filled with sand they will come open too easily. Discard them, since you don’t want sand in the sauce.