What would they be made of?

Would they be made of light material or would be heavy material. The problem is that most heavy materials are strong (not including gold). But, they are heavy so, the would way the spaceship down which would not be good as a escort ship. But, it would be good for freighter type ship. Luckily there is a material that is light enough so that one piece which would be 1 by 1 by 1/2 of a inch would be light enough to sit upon a dandelion. It would not be the main part of the space ship we still need an outer lining. "Fibrecore™ - As Strong as Steel, as Light as Aluminium…." Fibrecore™ - As Strong as Steel, as Light as Aluminium…. N.p., n.d. Web. 05 Feb. 2014.The outer lining composite would be fibercore a High strength, Light-weight, High Stiffness, High energy absorption, High noise and vibration damping properties. Which is very good outer lining for a space craft."Popular Science | New Technology, Science News, The Future Now." Popular Science. N.p., n.d. Web. 05 Feb. 2014.