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.
In a cooling climate, a good blanket of attic insulation helps keep the house cooler and reduces the load on air-conditioning equipment. Most attics are insulated with blown-in loose cellulose (R-3.5 per inch), blown-in loose fiberglass (R-2.5 per inch) or fiberglass batts (R-3.2 per inch). Cellulose is recycled newsprint treated with a fire retardant. Fiberglass is just that--thin fibers of glass that trap air.