Dedicated reagents make up most of this class — items whose only purpose is to be consumed by a recipe or a game system. Their value is entirely derivative: each reagent is worth what the things made from it are worth, minus the rest of the material bill, so reagent charts tend to shadow the markets of their end products with a short delay. That derivative pricing makes them a useful early signal, too — when an end product's market tightens, the reagents feeding it move first, and on the hourly editions the lag between the two charts is often a matter of hours.
Context tokens and keystones form the smaller subclasses, tied to specific game systems rather than open-ended crafting. Supply for these is usually gated by how the game hands them out, which produces stepped, event-driven charts — flat lines punctuated by moves when a patch changes the faucet.
Historically, 'reagent' also meant the class-specific spell materials every caster bought by the stack — a priest's candles, a paladin's symbols, a shaman's ankhs — and the classic editions preserve that era's economy: small items bought steadily, in stacks, every week, with some of the most metronomic demand curves in the catalog. Vendor supply anchors most of them, so auction listings price as a convenience markup over the vendor — and when the markup stretches too far, buyers simply walk to the vendor and the listing sits. The edition selector on each item's price-history page keeps the classic and Retail reagent markets from blurring together.
A small class rewards precision: with few items and thin books, one large posting can move a reagent's apparent price dramatically. The quantity-listed figure and the history chart on each detail page distinguish real repricing from a single seller's inventory dump. The "Browse subcategories" links below separate reagents, context tokens, and keystones into their own tables.