Lithofacies and Petrophysical Properties of Portland Base Bed and Portland Whit Bed Limestone as Related to Durability

This study focuses on the differences in lithofacies and petrophysical properties of Base Bed and Whit Bed Portland limestone and the presumed relationships between these characteristics and the durability of this building stone. As Portland limestone probably will be used as a stone for several restoration projects in the Netherlands in the...

Black Weathering of Bentheim and Obernkirchen Sandstone

Black weathering of sandstone in monuments is widespread. Some objects owe their name to it, like the Porta Nigra in Trier (Germany). Other than the black gypsum crusts common on limestone, the black weathering layer on sandstone is rather thin and well adherent. Formation of such layers on Bentheim and Obernkirchen sandstone, both widely used...