The present invention relates to proppants which can be used to prop open subterranean formation fractions. Proppant formulations are further disclosed which use one or more proppants of the present invention. Methods to prop open subterranean formation fractions are further disclosed. In addition, other...http://www.google.se/patents/US20060177661?utm_source=gb-gplus-sharePatent US20060177661 - Composition and method for making a proppant
