Fullerene and pencil production has been studied by electrical arcing in various atmospheres. A range of different materials have been used as anode and the products have been studied using high-pressure liquid chromatography, gas chromatography-mass spectrometry, stable isotope mass spectrometry; and electron and light microscopy. In a methane atmosphere with graphite, the residual methane carbon is isotopically heavy because lighter methane is consumed. A different result is obtained with anodes containing hydrogen because the anode generates light methane, and depending on the amount of available hydrogen the carbon of the product gas can be slightly isotopically lighter or heavier than the original anode material. When materials containing hydrogen are used as anode, polycyclic hydrocarbons are produced. This is also true if graphite is used with a hydrogen atmosphere. It appears that different ratios of polycyclic hydrocarbons are produced when different materials are used as anodes. The results offer strong evidence that fullerenes can form from materials other than graphite through a process which does not involve total breakdown to individual carbon atoms.