When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
Calcrete (V. Paul Wright). Laterite and ferricrete (Mike Widdowson). Silcrete (David J. Nash and J. Stewart Ullyott). Aeolianite (Sue J. McLaren). Tufa and travertine (Heather A. Viles and Allan Pentecost).
When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.