Commodity money cans or foil pouches of mackerel fish fillets, which have a fairly standard cost and are easy to store. These may be exchanged for many services in prisons where personal possession of currency is prohibited. In situations where the commodity is metal, typically gold or silver, a government mint will often coin money by placing a mark on the metal that serves as a guarantee of the weight and purity of the metal. In doing so, the government will often impose a fee which is known as seigniorage. The role of a mint and of coin differs between commodity money
Ultra-high-purity steam for oxidation and annealing processes are commonly used to generate TCO layers and modify crystal structures via grain size or defect repair. The ability to deliver water vapor free from atmospheric contaminants is critical to film integrity. The ideal water vapor for industrial manufacturing processes is extremely pure, moderate in temperature and free of extra oxygen or water microdroplets. In addition, this water vapor is ideally delivered in a range of flow rates from sccm to slm, into vacuum or atmosphere pressure environments for days or weeks at a time. Purity is paramount in avoiding contamination. Purity can be achieved by blending pure gases