INTRODUCTION: Limestone has many uses in addition to aggregate, dimension stone, and cement raw material, which are its principal uses in Indiana. Some uses, such as filtering, do not require stone of high chemical purity, but many uses do. Because the equipment necessary to quarry different grades of limestone is the same, a deposit that contains a large reserve of stone meeting the most stringent specifications is potentially more profitable than a similar deposit of stone that meets only minimum specifications. Stone suitable for agricultural and fluxing purposes, but most stone suitable for agricultural is not suitable for glass or fluxstone. This report therefore is devoted to high-calcium limestone and high-magnesium dolomite even though they may serve a broad spectrum of uses that do not require high chemical purity.