Nice way to put any excess lemons to one side.
Ripe unblemished lemons
Put the lemons into a bowl and cover with water. Leave for 3 or 4 days, changing the water occasionally.
Have wide mouthed jars ready. Hold the lemon upright, with the stem bit sitting on the chopping board, Make two cuts, in a cross, not quite cutting all the way through the lemon. The result being kind of like the petals of a flower. The lemon should still be joined at the base, but you should be able to open it up to push in the salt.
Gently open the quartered lemon and push in a scant dessertspoon of rock salt between the incisions. Push the closed lemons down into the wide mouthed jar, using a wooden spoon handle to guide them snugly into the gaps.
Pour over water, till the lemons are covered, then add a finger of olive oil to the surface.
Leave to preserve for at least a month in a darkened place.
I tried a more spicy version this year with a few lemons. Same procedure, but I popped in cardamon seeds, chillies and bay leaves, then topped up with hot water before capping.