here in wellington 'bins' are tubs of good quality cannabis oil (commonly made with isopropyl) the bin itself is usually those daily dispensary medication tubs or gelcaps filled with cannabis 'gold oil'!
Yep can use butane to make oil but it actually tastes quite harsh!! (after trying xylene, toulene, acetone + butane), isopropyl is mostly preferred here in nz for making cannabis oil! and only use icecubes for making hash..