The invention comprises a composition comprising hyaloclastite having a volume-based mean particle size of less than or equal to 40 m. The invention also comprises a cementitious material comprising a hydraulic cement and hyaloclastite, wherein the hyaloclastite has a volume-based mean particle size of less than or equal to approximately 40 m. The invention further comprises a cementitious-based material comprising aggregate, a cementitious material comprising a hydraulic cement and hyaloclastite, wherein the hyaloclastite has a volume-based mean particle size of less than or equal to approximately 40 m and water sufficient to hydrate the cementitious material. A method of using the composition of the present invention is also disclosed.

The invention comprises a composition comprising hyaloclastite having a volume-based mean particle size of less than or equal to 40 m. The invention also comprises a cementitious material comprising a hydraulic cement and hyaloclastite, wherein the hyaloclastite has a volume-based mean particle size of less than or equal to approximately 40 m. The invention further comprises a cementitious-based material comprising aggregate, a cementitious material comprising a hydraulic cement and hyaloclastite, wherein the hyaloclastite has a volume-based mean particle size of less than or equal to approximately 40 m and water sufficient to hydrate the cementitious material. A method of using the composition of the present invention is also disclosed.

The invention comprises a composition comprising hyaloclastite having a volume-based mean particle size of less than or equal to 40 m. The invention also comprises a cementitious material comprising a hydraulic cement and hyaloclastite, wherein the hyaloclastite has a volume-based mean particle size of less than or equal to approximately 40 m. The invention further comprises a cementitious-based material comprising aggregate, a cementitious material comprising a hydraulic cement and hyaloclastite, wherein the hyaloclastite has a volume-based mean particle size of less than or equal to approximately 40 m and water sufficient to hydrate the cementitious material. A method of using the composition of the present invention is also disclosed.

Disclosed herein are cement compositions and methods of using set-delayed cement compositions in subterranean formations. In one embodiment, a method of cementing in a subterranean formation is described. The method may comprise providing a set-delayed cement composition comprising water, pumice, hydrated lime, and a set retarder; activating the set-delayed cement composition with a liquid additive to produce an activated cement composition, wherein the liquid additive comprises a monovalent salt, a polyphosphate, a dispersant, and water; and allowing the activated cement composition to set.

The present invention relates to a process for producing calcium silicate hydrate under hydrothermal conditions, wherein an organic compound is added in at least one of the process steps and wherein the organic compound has a molecular weight of 100 to 600 g/mol and from 0.02 to 0.035 functional groups per gram of the organic compound, wherein the functional groups being selected from OH, COOH, COOM.sub.a, SO.sub.3H or SO.sub.3M.sub.a, or C(O)H, wherein M is hydrogen, a mono-, di- or trivalent metal cation, ammonium ion or an organic amine radical and a is , or 1. Further the invention is directed to the calcium silicate hydrate produceable according to the process of the present invention and its use as curing accelerator for hydraulic binders.