Criminalistics II Chapter 15

Most glass today is _____.

Is considered class evidence

Safety glass was discovered in _____.

1903

The primary ingredient in glass is _____.

Silicon dioxide

The _____ is determined by dividing the speed of light in a vacuum by the speed of light through a particular substance.

Refractive index

When glass breaks, small particles, called _____, are thrown back in the direction of the source of the breakage.

Backscatter

The only method that can produce individualized glass evidence is called a _____.

Fracture match

_____ is used to determine the refractive index of a glass fragment.

GRIM

Currently, the strength of normal glass products we use is _____ pounds per square inch (psi).

10,000

As a bullet passes through glass, _____.

The exit hole is larger than the entrance hole

Heat fracture patterns are _____ patterns.

Irregular, wavy

A Becke line appears _____.

In the liquid on the outside edge of the glass if a medium has a higher refractive index

The density of glass is calculated by _____.

Dividing the mass of a substance by its volume

Soda-lime-silica glass _____.

Is the most prevalent form of glass used for windowpanes

Laminated glass _____.

Consists of two or more panes of glass bonded by a plastic middle layer

Adding cobalt oxide to a glass mixture _____.

Produces glass that is a purple-blue color

Bulletproof glass was produced _____.

To protect the Mona Lisa in the Louvre

Nature forms glass _____.

From lightning strikes or volcanic eruptions

When collecting glass evidence, _____.

Separate glass by size, color, and texture

Glass fragments found in the head wound of a victim is believed to be bottle glass. No glass evidence is found at the location where the body was found. Detectives find glass at another location and want to know if the glass is consistent with the glass found in the victim's wound. Technicians in the lab determine that the fragments from the new location have a mass of 9 g and a volume of 3 mL. Based on this finding, _____.

The new glass fragments are not consistent with bottle glass

At a crime scene, the window pane of the front door is broken. Glass is strewn on the floor just inside the doorway. Investigators collect the glass as evidence. After testing, the glass evidence from the scene is determined to be window glass. Police search the house of a suspect. Detectives find debris on a pair of hiking boots. The debris is identified as glass, and when questioned, the suspect explains that he dropped and broke a lead crystal vase. The glass evidence from the suspect's hiking boot _____.

Will be nearly invisible in cinnamon oil if its source is lead crystal