A personal note on these awards: These awards have absolutely no effect on the game. Though the Terminator Honors and the Purity Seal are "Wargear" in the Codex that does have a game effect, I prefer to think of them as attributes the award was given for. Therefore, a Marine showing great combat ability (+1 A) would be awarded Terminator Honors, and a Marine or squad with great loyalty and faith in the Emperor (3D for pursue/fall back) would be given a purity seal.
The display of these awards is up to the individual Marine. They may wish to display them or not, or even to display a lesser award in favor of the greater one. Some of the awards have several forms, so the Marine can choose to display the standard award, or a more or less fanciful display may be selected.
This is the Crux Terminatus. More commonly known as Terminator Honors.
It is awarded to Marine heroes who have shown great combat and leadership ability. Receiving this award is a prerequisite to being selected into one of the Terminator Units of the Crusade.
This is also the Crux Terminatus, or Terminator Honors.
The bottom part of this Crux Terminatus is pointed, indicating a greatly honored recipient, possibly one who has received the honor numerous times. This is required to become the leader of the Crusade’s Terminator Unit, and this leader receives the additional gemstone to indicate that honor.
This is an honor plate awarded to Marines to honor their valor in combat.
To become an officer requires this award.
This is also an honor plate, though this plate is reserved for officers, including sergeants.
Once a Marine becomes an officer, his silver honor plate is exchanged for this gold one.
This is a purity seal, given to show extreme loyalty and faith in the Emperor.
It can be awarded several times, and an additional purity seal is given each time.
This is the Laurel of Life. It is awarded to Marines whose action resulted in the continuing life and service of another Marine. From the white armor this award is displayed on, you can tell it was awarded to an Apothecary. This is not uncommon, in fact all Apothecaries will have been awarded this honor before officially becoming an Apothecary. However, this award is not limited to Apothecaries, any Marine may be granted this honor.