On the other hand, what makes the item desirable may not be the price, but the perceived price. Suppose the graph to the right, illustrates the market for Rolex® watches with ruby encrusted bezels. Suppose D₁ is the demand curve, if most people think these are $150,000 items. D₂ is the demand curve when people believe they cost $300,000. A change in the perception of what such watches cost leads to a shift from D₁ to D₂, leading to a higher price. However, for a given perception of the price, the demand curve could still be downward sloping. If this is how it works, if buyers of ruby studded Rolex® watches still want the best deal, then this isn't an exception to the law of demand at all.