This invention relates to an improved method for treating clay materials to prepare a super-active catalyst for use in catalytic conversion of organic materials such as, for example, hydrocarbon compounds, heavy crude petroleum stock and kerogen, wherein when a clay material is contacted with a solution containing cations selected from the group consisting of transition metal ions, aluminum ions, hydrogen ions, ions of metals from Group IIB of the Periodic Table of Elements and a combination thereof with each other, the clay material is in the raw state and maintained at a temperature not exceeding about 100.degree. C prior to and during the contacting with said solution and thereafter heating said exchanged clay material to a temperature of at least about 50.degree. C but not exceeding about 250.degree. C in the presence of air and/or organic material which is to be catalytically converted. Further, this invention relates to the clay material which is the product of the above improved method and to converting organic materials such as, for example, hydrocarbons, heavy crude petroleum stock and kerogen, by contact at low temperature, e.g. from about 50.degree. C to about 250.degree. C, with said clay material.