Ontario introduced time-of-use (TOU) pricing to reflect the costs of producing electricity at different times of the day. There are three TOU periods: 1  Off-peak, when energy demand is low and less expensive sources of electricity is used. 2  Mid-peak, when the cost of energy and demand are moderate. 3  On-peak, when demand is highest and more expensive forms of electricity production are used.
Sheen Obsidian-this is a family of valued types which consists of sub-types categorized according to the effect or color displayed. Microscopic bubbles and/or crystals of Feldspar or Mica trapped in the Obsidian result in a chatoyant (irridescent) sheen when the stone is viewed from certain angles.heen Obsidian-this is a family of valued types which consists of sub-types categorized according to the effect or color displayed. Microscopic bubbles and/or crystals of Feldspar or Mica trapped in the Obsidian result in a chatoyant (irridescent) sheen when the stone is viewed from certain angles.
Obsidian was so named from its resemblance to a stone found in Ethiopia by Obsius. It was used in antiquity for amulets and necklaces. Obsidian is a naturally occurring volcanic glass. It is usually an opaque black or grey but may be yellow, red, greenish brown. Obsidian may have an iridescent sheen caused by inclusions. Obsidian is used for ornamental purposes and as a gemstone. Many colored glasses are sold as obsidian often claiming to be natural.