Tin foil hat to achieve this effect. A belief also exists that aluminum foil is a protective measure against the effects of electromagnetic radiation (EMR) for many unspecified EMR frequencies. Despite some allegations that EMR exposure has negative health consequences, no published experimental scientific evidence has established that tinfoil hats are effective. In 1962, Allan H. Frey discovered that the microwave auditory effect (i.e., the reception of the induced sounds by radio-frequency electromagnetic signals heard as clicks and buzzes) can be blocked by a patch of wire mesh (rather than foil) placed above the temporal lobe. Foil hats have appeared in the films
Tin-glazing of tin glazes may differ in different sites and periods, the process of the production of tin glazes is similar. Generally speaking, the first step of the production of tin glazes is to mix tin and lead in order to form oxides, which was then added to a glaze matrix (alkali-silicate glaze, for example) and heated. After the mixture cooled, the tin oxide crystallises as what has been mentioned above, therefore generates the so-called white tin-opacified glazes. Besides, the body of tin-opacified wares is generally calcareous clays containing 15-25% CaO, of which the thermal expansion coefficient is close to that