Glass and Paint

Glass

When glass is broken, minute fragments are created that can travel backwards towards the breaker or be picked up as an individual contacts a broken edge or treads on a nearby surface covered with such fragments. When transferred to clothing, these fragments can persist for a period of time, this being dependant on the type of clothing and the retentive ability of the material. As glass can be broken during the commission of a wide variety of crimes including burglary and car-related crime, such evidence can be extremely useful to the investigator.

Due to the differences in manufacturing between different types of glass, using a measure of refractive index and chemical composition, an accurate comparison can be made between glass fragments and the original glass window or headlight for example. The evidential weight of these findings is considered in terms of both the rarity of the type of glass and the number of fragments found on a person's clothing and footwear. This is because most commonly, glass fragments on the surface of clothing are lost within a few hours of an individual being close to a breakage.

At Manlove Forensics we are able to carry out examination of items for glass and subsequent comparison with a suspect glass sample. We can also review the findings of other scientist's work carried out at other laboratories or carry out testing on glass samples that are new to an investigation and compare the results to the original work carried out.

Paint

As paint covers so many surfaces, whether they be vehicles, window frames, tools or walls, the comparison of trace quantities can be very important to a case.

Paint analysis can look at either the physical appearance (colours and layers) or the chemical composition. As a painted surface can often be covered with a number of layers, when these are damaged, flakes can be removed. If these are found, they can be matched both in terms of layers and of the broken edge of the fragment back to the original surface. These can be unique matches and deterministic of origin.

As paint is made of a cocktail of different chemicals such as pigments, modifiers and binders, an analysis of the chemical composition can create a chemical signature that can be compared with reference samples.

Manlove Forensics are able to carry out the review and further testing of paint samples to aid your investigation.

Tel: 0845 371 2486