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.
If we stretch the quartz fiber or phosphor bronze beyond the elastic limit, a small permanent set occurs. Quartz fiber and phosphor bronze are nearest approach to the perfect elastic body. A body is said to be perfectly elastic if it completely regains its original form when the deforming force acting on it is removed. Since no material can regain completely its original form, the concept of perfect elasticity is an ideal concept. Cheers!!