I cannot remember the correct name for this stuff but is it any good? I need to patch (12" x 6") a path that has little traffic. How deep do I need to dig and do I need to do any more prep work than dig to a suitable depth? My main questions are is it any good and will it last? I presume I just tamp it down with something suitable to be level with the surrounding Tarnmac. If it helps it is at the edge and it will butt up against edging stones that are fixed 'edge uppermost'. Hope that all make sense to people.
TIA
John