Hopefully the ones that contain the ore your chasing Darryn!
Are you referring to cap rock (sitting above ground) or rock dug from pits, shafts etc?
Besides oxygen, the most abundant element in the earths crust is Silicon and an oxide of Silicon is Quartz (Silicon Dioxide SiO2, or Silica).
If you know how gold is formed beneath the earths crust, you will understand that the
'Structure' the rock is involved with is the key, more than the type of rock itself.
Gold is not fussed about its host, but rather the conditions its host formulates for it. Metamorphosed rock usually contains structure (gneiss, slate, marble, schist, and quartzite etc)
By structure I mean, Foliation, sheer zones, bedding etc. so target rock that is involved with these types of structure. (Hence you speak of 'Honeycombing')
Its a common misconception that gold nuggets found have cooled after travelling in a molten state.....this is not so!
Gold is actually dissolved in hot salty water along with many other elements (mainly Silicon) to form a complex ionic solution deep beneath the earths crust.
These solutions will take the least path to resistience (foliation, sheers in host rock etc) under heat and pressure, this is usually upwards towards the surface giving less pressurized, cooler zones. When these solutions cool, they crystalize to form solids (This is why gold is commonly found in quartz or Silica).
Study these basic theories some more and it will soon become very clear to you what to look for, when zoning in on specimens to crush and how to obtain them.
Hope this makes sense to you?
Regards