Red Sandstone: D&D?

Why isn't the daily 50 red sandstones you can mine not considered a D&D? It's something you can do once a day so it annoys me how it isn't in my D&D in the RS Toolbar. Anyone know why?

 

Probably because it does not give you an experience boost apart from the experience itself from mining it and the high mining level required? I don't know, try asking JaGeX. We can only assume and assuming, as the saying goes, makes an ass out of u and me.