"Ah, colorful and shiny stones you call them, how fascinating. You may not have a term for them, but each stone is called differently according to their colors here in our Kingdom. For instance, this blue wonder in my hand is called a sapphire, whilst the stones embedded in your shaman's staff are called emeralds. The nobles of the Kingdom are indeed fond of it, more so that they have many names."
"I am intrigued, what does it have to do with our negotiations?"
"I suppose I would stop beating around the bush now. This tiny sapphire in my ring costs thousands of times its weight in gold. This gem costs about three thousand gold pieces alone, enough to feed a modest village for several months, or perhaps fund a small army for a short campaign with weapons, training and all. Albeit a gemstone's worth is measured by its lack of impurities, an emerald is still rarer than a sapphire such as this one, thus even more expensive once it is refined and processed."