Lerma river system, the organization H2O Lerma Con Encanto is seeing results with eggshell and volcanic rock filters.

Volcanoes are natural laboratories in which ... The nature of their solid products, lava, scoria, lapilli, and ashes, have been carefully studied, but their gaseous products are less easily ...

These brick-shaped building blocks are known as Copperhouse slag or scoria blocks. This is a typical example. They were cast from the residue of the copper smelting works that operated at ...