Why choose? There is such a thing as diamond aerogels: http://www.popsci.com/technology/article/2011-05/new-diamond-aerogel-least-dense-diamond-ever-made http:

Why choose? There is such a thing as diamond aerogels: http://www.popsci.com/technology/article/2011-05/new-diamond-aerogel-least-dense-diamond-ever-made http://www.popsci.com/technology/article/2011-05/new-diamond...