Once upon a time, there lived ancient peoples who wanted to symbolize eternal love. They believed that symbols held special, magical powers. For these ancient people, a circle represented eternity, and it was not long before lovers exchanged small rings that fit on one's fingers. At first the people used grasses, bone and wood as rings, but these were no good because they could break or come undone easily. This was a very serious problem for the ancient peoples, because if the symbol itself was broken, that meant the powers of the symbol were broken.
As the ages passed, the ancient peoples searched far and wide for a way to create the perfect symbol of love. Civilizations rose and fell; great empires ruled the world and then receded back to their origins. Religions were invented then replaced; gods created and then forgotten. Yet the power of symbols was never ignored, and the search never ceased. The people found mysterious metals in the earth, some rare and others common. They discovered how to forge these metals into newer, stronger, finer rings. For a while they were happy, but as it were, all their new rings eventually became decayed and broken by the passage of time and the adventures of life. The symbols were better, but they were still breaking; and so the search went on for thousands of years, for people everywhere in this world, to this day.
It sounds like a fairytale, and yet that's essentially the true history of rings - some say it started 4,800 years ago. It's a history that's still being written, because we're still trying out new metals and other materials year after year. Diamonds were discovered early in human history to be the hardest material, able to be cut only by another diamond (diamond is adapted from the Greek word adamis, meaning "unbreakable"). However, they are too small to be cut into a ring, so it became practice to put diamonds onto rings.
However, the ring itself; the symbol representing eternity; really needs to last for an eternity. But they say nothing is forever. Is there anything out there that can actually last forever?
As of very recent history, the search may be over. Titanium has properties that range from highly useful to downright bizarre. For example, while most metals will corrode away over time, titanium actually grows its own protective layer. While most think of titanium as a metal, it's actually an element and is found in many things, even organic matter like some plants. The growth rate of this protective layer is so slow that it's not perceptible to the human eye, but it thickens over a period of years which severely impedes any kind of degradation. Potentially, this protective behavior could go on indefinitely, making it invulnerable to any natural degradation at all.
If this is in fact the end of the search, then this is what it has come to: a ring that is strong, weightless, unbreakable, and beautiful. Just like true, eternal love.