Each Chevalier is unique in his or her own way. Including their ranks. The ranks go from the lowest Sothis, to the highest of ranks, Sammas. Very few become a Sammas, but those that do, are highly honored amoung other Chevaliers.
This elite army of the King only find out that they are Chevalier's after the right of ascension, which is usually about when they turn about ten or twelve years old. A small jewel can be found between where the collarbones meet on their torso, seemingly sunk firmly into their skin. Below, is the heirarchy of these clans, the jewels that you would find on them, and a small description of each clan.
Sothis
Gem: Tiger's Eye
Sothis are the youngest and the least trained of the Chevalier. After they have found out that they are part of the elite army, they are brought to the training grounds of their specific clans. Here, they train for their own unique styles of fighting with higher ranks (usually the Glitnir). They take many years of training (most far away from home and families), to join the ranks of Areth. Which only comes with recommendation of a higher member in the clan, usually the one that he or she was being trained under.
Areth
Gem: Jade
The next highest rank is the Areth. They are still in the learning and training process, and are usually found with either a member of the Glitnir rank, or out with the likes of such as the Cereth, if they are lucky enough and have been trained well in the ways of their clan. Very rarely are either of the Sothis or the Areth ranks found on the battlefield, unless their numbers are needed. They are only to become a Glitnir when they have shown their own Glitnir "master" that they can handle their next task...to teach another.
Glitnir
Gem: Turquoise
To teach is to have given something back to the kingdom. If not our lives, then our wisdom and knowledge that was past down from out own Glitnir Masters. These men and women train those that will become the great Sammas' to come. They give of themselves, one student at a time. They live in small encampments with many other Glitnir's, along with their students. The training grounds are never far, as the Glitnirs are famous for waking up the young Sothis and Areth men and women for an early morning pratice. They are skilled, and if they so wish, move up quickly in the ranks themselves. Many though, stay with the students, unless needed to fight for the armies. One of the truely noble ranks.
Imbolas
Gem: Lupis Luzuli
The Imolas is the plateau of which many Chevaliers come to, and stop....going no further up the heirachal ladder. Having been taught, and then had taught another, these men and women use their skills to fight off the enemy. The bulk of the Chevaliers are found here, where they find that they are more useful to the Kingdom. Only after many fierce battles and the recommendation of those in a higher rank, can they too, become either a Cereth or a Sammas. Many, choose not to.
Cereth
Gem: Opals 
Many Cereths you could say would be the Captains of today. The great leaders of small armies, those that know the territories of Astoria and its' enemies well enough to lead their men into a battle and not have many casualties. They are wise, courageous, and almost fearless. These are the ones that many look up to as role models, and are not as "haughty" as some in the Sammas ranks. They are more down to earth, and tend not to let their ranking cloud their judgements. It is only by recommendation, or an order by the court that a Cereth shall become a Sammas.
Sammas
Gems: Star Ruby or Star Sapphire 
The elite of the Chevalier. Time and many battles are etched on their faces, many of them having lost friends, family and loved ones since they have been a part of their own clans. Many still fight the good fight, but many have either retired, or have become Admirals...those of which stand in the background and give out orders to the rest. They too, are highly regarded, and respected in every aspect. Some take this and use it to their advantage though, making some of the lower clans do their bidding. It doesn't last long, as another Sammas will step in and see that what is happening is stopped. They have respect for those that give it, and are very kind and almost noble, much like their now dead king.
