It contains minerals such as pyroxene, amphibole, feldspar and 63-68 percent silica. The eruption temperature for dacitic lava is 1,500 to 1,800 degrees Fahrenheit. Dacitic to rhyolitic lava is so dangerous because it contains a high amount of crystals.Mt. Vesuvius erupts according to the Plinian model of eruption.
Foil has low emissivity, so will greatly reduce radiative heat transfer (act like insulation). It should face the side that is supposed to be cooler. But foil will not reduce conductive heat transfer, so it must be used judiciously with something that reduces conduction.
Happily, your confusion and your concerns are mostly unnecessary. When insulations are compared, cellulose fiber insulation, a gray-white powder made from shredded recycled newspaper, emerges as the overall best choice. And where cellulose wonât work, there are other good, safe, products that can fill the gaps (literally). To understand why cellulose is the best insulation, compare it to its principal competitor, fiberglass. Cellulose and fiberglass together account for over 90 percent of insulation sales. Both insulations cost about the same, and both cost less than all their competitors.