Hellstone Bar. Hellstone Bars are made from 1 Obsidian and 3 Hellstone at a Hellforge. They are used to create Hellstone Tier items. Items made from Hellstone Bars are the highest quality craftable pre-hardmode items that require bars.
Unitary elastic means that elasticity is equal to 1. In case of price elasticity of demand, e = 1 implies that the percentage change in quantity demanded is equal to the percentage change in price of the commodity. Demand Elasticity is obviously negative. Elasticity = percentage change in quantity demanded / percentagechange in price. Even though perfect real life examples would be tough to list, a close example can be a 1$ increase in price of a good leads to a unit fall in its quantity demanded.
Economics Help states that price elastic goods are those that are easily affected by changes in prices, with demand changing along with the rise and fall in he price. Price inelastic goods are those that are difficult to replace or so low costing that a change in the price has little effect on the overall demand of the product or service.