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Following the atomic bombing of Hiroshima, it was discovered in 2016 that between 0.6% and 2.5% of sand on local beaches was fused glass spheres formed during the bombing. Like trinitite, the glass contains material from the local environment, including materials from buildings destroyed in the attack. The material has been called hiroshimaite ...
An hourglass (or sandglass, sand timer, or sand clock) is a device used to measure the passage of time. It comprises two glass bulbs connected vertically by a narrow neck that allows a regulated flow of a substance (historically sand) from the upper bulb to the lower one due to gravity. Typically, the upper and lower bulbs are symmetric as they ...
Vitrified sand is a type of natural glass, contrasted with manufactured glass in which soda ash or potash are added to lower the melting point. Pure quartz melts at 1,650 °C (3,002 °F). There are several natural processes that produce more or less melted sand and one man-made form: Fulgurite is sand fused by a lightning bolt hitting sand.
Sand is a granular material composed of finely divided mineral particles. Sand has various compositions but is defined by its grain size. Sand grains are smaller than gravel and coarser than silt. Sand can also refer to a textural class of soil or soil type; i.e., a soil containing more than 85 percent sand-sized particles by mass. [2]
A lump of glass was found at Eridu in Iraq that can be dated to the twenty-first century BC or even earlier; it was produced during the Akkadian Empire or the early Ur III period. [4] The glass is of blue colour, which was achieved with cobalt; such glass is generally known as Egyptian blue. Thus, such technique was attested in Eridu long ...
Sodium silicate glass-to-glass bonding has the advantage that it is a low-temperature bonding technique, as opposed to fusion bonding. [21] It also requires less processing than glass-to-glass anodic bonding, [ 23 ] which requires an intermediate layer such as silicon nitride (SiN) to act as a diffusion barrier for sodium ions. [ 23 ]
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"Still-Life with a Skull" by Philippe de Champaigne, c. 1671. The sands of time is an English idiom relating the passage of time to the sand in an hourglass.. The hourglass is an antiquated timing instrument consisting of two glass chambers connected vertically by a narrow passage which allows sand to trickle from the upper part to the lower by means of gravity.