Sorry should have qualified, both only 16 inch frames, cindercone and lavadome both weigh just under 4.2 pounds bare weight, fully painted.
An 18 is considerably bigger than a 16, as the ctc on a 16 seat tube is only 13 inches and top tube 21. Both weighed on digital scales so won't be far out. I had an 18 which was too big and this weighed 4.6 on the same scale. But getting sidetracked here!
I was told by a dealer once that many Kona frames were re badged in the factory if they were short of a specific model and that only the components were different and the Explosif had different tubes. The Kilauea picture above has the same drop outs and detail as my more recent Lavadome, so maybe they were the same frame?
I gather it was luck of the draw sometimes you got a better or lower frame with different paint on it!