Indian Sandstone Resiblock Sealant 28 August 2013 by Rob Martin News Indian Sandstone and other forms of natural stone are beautiful hard landscaping mediums. As with all external paving this investment can be protected. Resiblock Indian Sandstone Sealer is suitable for application to most forms of natural stone providing long lasting protection. •Stain resistent •Colour enhancer •Resists algae growth •One coat •Lasts up to 5 years •Suitable for use with most forms of natural stone