Blast furnace slags were partially replaced by artificial and natural pozzolanic materials, such as pozzolan , fly ash and zeolite,to produce alkali activated slag cement(AASC).
The alabandite and getchellite of hydrothermal origin, cement anatase of alkaline volcanic origin, and the high content of chlorite in coal were fist found in coals.
Scientists on Wednesday raised the alert level for Anak Krakatoa and Tangkuban Prahu -- which regularly spew gas and rumble -- from "normal" to "warning," the middle of three alert levels.
In March 2007 a mud flow, or "lahar" flowed down the side of the mountain after the crater lake overflowed, and large eruptions in 1995 and 1996 blanketed the surrounding area in ash.