REVIEWS in MINERALOGY and GEOchEMIStRY

ON THE COVER: Background image: polymict aggregate in concrete, containing several types of sand-/siltstone in various colors, black lydite, chert/fl int in various shades with and without cortex, white vein quartz and reddish quartzite, etc. Several lithologies behave alkali-reactive as revealed by internal cracking, presence of dark rims, etc. © Maarten ATM Broekmans. Front cover, top: Panorama of the Three Gorges Dam in China facing south, one of the largest concrete structures in the world, still under construction in October 2004. The dam with the Chinese characters on the right was temporary only, and was removed by blasting when the main structure was fi nished in 2009. © Maarten ATM Broekmans. Front cover, bottom: Rosette of layered doublehydrate (LDHt) phase in CAC. © Herbert Pollmann.