What do the Silmarils Symbolize?

 In an extremely literal sense, the Silmarils are just shiny glowing rocks. If that was all they were, then characters wouldn’t be willing to start wars, kill, and die to get them back. So, what is it that they’re really trying to recover?

Here are two possible interpretations: 

1.) The Silmarils represent (moral) perfection

The Silmarils capture the light of the two trees Laurelin and Telperion in Valinor — the light of an un-marred world. When the trees were destroyed by Morgoth (a personification of evil), that pure light (symbolizing perfect goodness) was compromised, and — at least to the Noldor who left Valinor in a time of distress — so was that perfect world. By winning the Silmarils back, they would be regaining perfection.

This would make sense especially in the context of Eärendil and Elwing, Maedhros, and Maglor. Eärendil and Elwing selflessly brought a Silmaril to Valinor with the hopes of redeeming the Eldar and Edain — somewhat restoring “the light”. On the other hand, Maedhros and Maglor, who committed murderous actions in pursuit of the Silmarils, were no longer fit to hold them — they could not reach perfection because they were not wholly clean.

2.) The Silmarils represent victory 

The Noldor didn’t declared war on a specific people, they declared war on an individual and all that he represents. So, when the enemy places the king’s jewels, the famous gems admired by even the Valar, on his filthy crown it must certainly be a heavy insult. The war wouldn’t be over the Silmarils, it would be about the struggle between good and evil, where the gems are almost like a trophy irrelevant to the cause but important as a device representing complete victory. 

This fits well with the ending of the story: when Morgoth is defeated, the remaining Silmarils are gained by the Hosts of the Valar. Even after they were stolen again by Fëanor’s sons, nobody really cared. Nobody goes into hysterics or declares war when Maedhros casts one into a fire and Maglor casts one into the ocean, because they had already won. Victory was already their’s and they don’t need the Silmarils to prove it anymore.