SilKonfig

'world':  #The name of the world.
  drops:
    GRASS_BLOCK:  # ID of the broken block
      DIRT:  # ID of the dropped block
        - 20%  # Drop percentage
        - 3  # Drop amount
      DIAMOND:
        - 50%
        - 1
      SPRUCE_LOG:
        - 20%
        - 5
      messages:  # You can set a custom message on silk break.
        - '&2You cannot use Silk Touch on a block of grass.  You get a simple dirt block.'

    DIAMOND_ORE:
      DIAMOND:
        - 50%
        - 2
      DIAMOND_ORE:
        - 50%
        - 1
      # You won't get a message if you don't put it.

no-permission: '&4You have not the permission to break this block.'
no-permission-action: 'none'    # You can set either 'prevent breaking' or 'none'