Rocket fuel. Scanning Electron Micrograph (SEM) of crystals of solid rocket fuel, also called rocket propellant. These crystals are of a double based- type of solid rocket fuel made of a nitrocellulose-type of gunpowder dissolved in nitroglycerine. Both these ingredients are explosives and extremely hazardous to handle and store. Rocket propellant ingredients have particular functions such as fuel, oxidiser, binder and these two ingredients fulfil these requirements. Magnification: x3000 at 8x10 inch size.