Gresco Labstone is a special, high density formula that is harder than most regular lab stones. Our lab stone mixes creamy and stacks very well. It can be used to pour model bases, opposing models, or study models. The hardness of this stone will withstand the vacuum forming process when making bleaching trays or night guards. Setting expansion is approximately .10%. The color is Natural, which means that there are no added colors. The set time is “regular”, so the initial set is about 16 minutes. All of our die stone and lab stone products are based on proprietary formulas developed by Gresco Products and made here at our facility in Stafford, Texas. Because of our exacting manufacturing and blending techniques we are able to offer a good, consistent product. 50 pounds per package. Made in the USA.