Abstract: A pigment paste and a method for making the same that alters the appearance of concrete such that, after the concrete sets, it resembles natural stone concrete sets, it resembles natural stone (e.g., marble, granite, sandstone, bluestone, etc.) without separately applying a finish of any kind to the concrete are provided. The pigment paste preferably comprises a filler, a pigment, an anti-foaming agent, a surfactant, and water. In some embodiments, the surfactant is a water reducing admixture. A concrete compound having a finish resembling natural stone is made by combining the pigment paste with a concrete mix, which includes a cementitious material with aggregate and water, and a chemical admixture. Upon adding the pigment paste and mixing it, the cementitious material is allowed to set, where, after it sets, the concrete has a finish resembling natural stone.

Abstract: A non-chloride powder admixture that, when added to concrete, substantially reduces the setting time for concrete and increases the strength of the concrete is provided. The powder admixture preferably comprises a calcium aluminate compound (e.g., SECAR 51) and a lithium carbonate compound. The calcium aluminate compound preferably has at least 51.7% alumina. In some embodiments, a surfactant may be added to the mixture of the calcium aluminate compound and the lithium carbonate compound. In some embodiments, the powder admixture may be blended with a cementitious material, such as fly ash or slag. Upon adding water to the admixture and cementitious material mixture, both the setting time of the mixture reduces and the strength of the mixture increases as compared to the setting time and strength of the cementitious material without the powder admixture.