Properties of Glass and Glass Analysis Techniques

Physical property

Describes behavior of a substance without reference to any other substance

Chemical property

Describes behavior of a substance when it combines with another substance

Weight

Force with which gravity attracts a body

Mass

Constant property referring to the amount of matter an object contains

Frequency

Number of waves that pass a given point per unit of time

Wavelength

Distance between crests of adjacent waves

Photon

Discrete particle of electromagnetic radiation

Electromagnetic spectrum

Entire range of radiation from cosmic rays to radio waves

Amorphous solid

Solid with random or disordered arrangement of atoms or molecules

Crystalline solid

Solid with regular arrangement of atoms

Fahrenheit Scale

Temperature scale defining melting point of ice as 32° and boiling point of water as 212°

Celsius Scale

Temperature scale defining melting point of ice as 0° and boiling point of water as 100°

Becke Line

Bright halo observed near border of a particle immersed in a liquid of different refractive index

Dispersion

Separation of light into its component wavelengths

Refraction

Bending of a light wave caused by a change in its velocity

Density

Physical property equivalent to mass per unit volume of a substance

Refractive index

Ratio of speed of light in a vacuum to its speed in a given medium

Soda-lime glass

Glass made by melting sand with metal oxides, including soda and lime

Borosilicate glass

Glass made by adding boron oxide to the oxide mix, used for automobile headlights and heat-resistant glass

Tempered glass

Glass with added strength through rapid heating and cooling of the surfaces

Laminated glass

Two sheets of ordinary glass bonded together with a plastic film

Radial fracture

Crack in glass that extends outward like the spoke of a wheel from the point of impact

Concentric fracture

Crack in glass that forms a rough circle around the point of impact

Flotation method

Method to determine a glass fragment's density by immersing it in a liquid with carefully adjusted density

Immersion method

Method to determine a glass fragment's refractive index by immersing it in a liquid with adjusted refractive index

GRIM-3 (Glass Refractive Index Measurement System)

a system to automate measurements of match temperature and refractive index for glass fragments

3-R rule

Radial cracks form a right angle on the reverse side of the force, helping determine the side a window was broken