Chapter 15 Flashcards
Additive color mixing
Adding together two colors of light to give a different color.
Proxy indicators
Small amounts of identifiable material from a specific location that can indicate with relatively high accuracy information about the location from which they originated.
Glass
An amorphous material composed primarily of silicon dioxide.
Laminated glass
A form of safety glass where a piece of clear plastic or resin is sandwiched or “laminated” between two pieces of glass.
Intrinsic properties
Properties that are the same no matter how much material is present in the sample.
Chemical properties
Properties that can be measured only by attempting to change the chemical identity of the material itself through some sort of chemical transformation.
Color
The way that our eyes and brain perceive different wavelengths of light in the visible range.
Physical properties
Properties that can be measured without changing chemical identity of a material.
Pigment
The portion of paint, consisting of very tiny particles of organic and inorganic colored compounds, that gives the paint its characteristic hue.
Plastics
Materials that can be molded; today they are most often made from high molecular weight polymeric compounds.
Concentric cracks:
Fractures in glass that form rings that approximately circle the point of impact.
Density
Defined as the amount of mass of a material contained in a particular unit of volume, or d = m/V.
Conchoidal marks
See “Stress-induced striations”.
Dye
A soluble compound that binds directly to the surface and does not require any medium to bind the colored material to the surface.
Geology
The detailed study of the Earth and its materials along with the physical processes that act upon them.
Float glass method
Method for producing flat glass where a layer of molten glass comes out of a furnace as a continuous sheet that is then floated onto a bed of molten metal, most often tin.
Floatation
A method for approximating the density of a sample by determining the density of a liquid upon which the sample will float.
Extrinsic properties
Properties that change if the amount of material in the sample changes.
Birefringence
A double refraction phenomenon in certain crystalline materials where the refractive index is different depending upon which direction the light goes through the crystal.
Becke line
The halo observed at the edges of a solid, transparent sample when in a liquid with a higher RI than that of the sample. An optical phenomenon used in measuring the refractive index of an object.
Borosilicate glass
Glass with boron oxide added to the silica to improve ability to withstand rapid changes in temperature.
Buoyancy
A method to determine the volume of an irregularly shaped object by determining the mass of the water (or liquid) displaced by the submerged object.
Binder
The portion of paint that suspends the pigment particles and helps to firmly fix them to the surface.
Radial cracks
Extend or “radiate” outwards from the central point of
impact, producing a star-like pattern.
Viscosity
The resistance of a liquid to flow.
Volume by Displacement
A method to determine the volume of an irregularly shaped object by directly measuring the volume of liquid it displaces when submerged.
Tempered glass
Glass that has been either heated or chemically treated to change the stresses within the glass to make it safer upon breaking.
Stress-induced striations
Rib marks that appear on the edge of broken glass.
Soil (dirt)
A mixture of inorganic (mineral) and organic components that are packed together relatively loosely with structural components of solid, liquid, and gaseous fractions.
Refractive Index
The ratio of the speed of light between two transparent substances (usually the air and another substance such as glass or plastic), calculated as velocity of light in vacuum (or air) divided by the velocity of light in the substance.
Subtractive color mixing
Occurs when mixing pigments together and arises from one color being removed from white light through absorption by the pigment.
