X-Ray Diffraction
The whole purpose of x-ray diffraction is to determine the atomic structure of a substance, but how does it work i hear you ask. By firing x-rays at a sample of the substance results can be recorded onto a sheet of photographic paper when said rays collide with the its own atoms.

The X-rays bounce off and form unique patterns on the photographic paper based upon the nature of the atoms they actually hit.

Electrophoresis
When it comes to DNA profiling there are a number of different procedures that can be conducted on biological matter in order to determine a genetic fingerprint. One of the ways that this biological matter is separated is through electrophoresis. Both blood and semen can be submitted to this process – it uses an electric current in order to separate the different sized molecules in proteins, enabling them to be submitted for further analysis.

Chromatography
There are a number of different methods that exist in chromatography, all of which are based around a similar scientific principle and all of which have been scientifically proven. It is primarily used to identify different chemicals as in dyes, drugs and residue found in dirt. It also has the ability to identify DNA, proteins and genes from tiny samples. At the end of the day the process is designed in such a way that it separates out the various components from each substance in order for them to be identified.

Spectrometry
After individual components of a sample have been separated is when this forensic method comes into its own. What it does is test a components light absorption and reflection qualities by by using a device called a spectrophotometer. By using this device, forensic experts are able to see exactly which colours of light are affected by a sample, and subsequently compare the obtained sample with samples of material they already have in their databases with results represented in graphs.

Mass Spectrometry
While it contains the title of the previous forensic technique, the actual methods utilised are completely different to its predecessor. Mass spectrometry uses high energy electrons in order to literally ‘knock’ electrons out of the samples molecules which in turn causes them to fall apart. After this process is completed a mass spectrometer uses an electrical or magnetic field to measure each individual pieces mass.

Particular molecules will always break into a predictable range of pieces with no chance that two different molecules will break into identical pieces. Given this, forensic professionals are able to take any sample of material and ascertain exactly what chemical components are within it.

Neutron Activation Analysis
This is one of the most amazing and accurate forensic techniques in the book – not that forensic techniques are ever inaccurate, but this particular method can detect whether atoms from a particular element are present in a sample down to levels as low as one part per billion. This particular forensic method exposes samples to gamma rays in order to look through to the centre of an atom within a sample thereby identifying what atoms are actually present. It is used to detect trace elements in not only drugs and gunpowder but also metals, paint, soil and hair.

But what is forensic ballistics exactly? What is included in this field?

First off, a definition; Firearms identification (forensic ballistics) is defined as “The identification of fired bullets, cartridge cases or other ammunition components as having been fired from a specific firearm.”
Technically the field of forensic ballistics falls inside toolmark identification, as the gun used, being of a harder substance than the bullets being fired from it, leaves its own unique markings on each round as it exits the barrel – just like a pickaxe when swung with force leaves markings on the stone it collides with.
In addition to the well known facets that a firearm examiner undertakes in their daily activities (comparing rounds recovered from victim’s bodies to rounds test fired in a lab) they are also responsible for:

1. Testing of firearms, making sure they function correctly.
2. Examining garments of clothing and other items for gunpowder residue and shot patterns in an attempt to establish the distance from the victim of the attacker.
3. Determining the manufacturer and the calibre of ammunition components including standard rifle or handgun rounds as well as shotgun/shell ammunition.
4. Determine what model or manufacturers weapon has fired a particular round or shell.

Further to these analyses firearms examiners are required to give written reports detailing their findings as well as give expert testimony in criminal proceedings.

In time, we plan to discuss the science of toolmark identification with a main focus on forensic ballistics as well as add additional educational resources and information on how to get into this field.