Masonry oven Masonry oven A masonry oven, colloquially known as a brick oven or stone oven, is an oven consisting of a baking chamber made of fireproof brick, concrete, stone, clay, or cob. Though traditionally wood-fired, coal-fired ovens were common in the 19th century, and modern masonry ovens are often fired with natural gas or even electricity. Modern masonry ovens are closely associated with artisanal bread and pizza, but in the past they were used for any cooking task involving baking. Masonry ovens are built by masons. Humans built masonry ovens long before they started writing. The process began as soon as
Rare-earth magnet Rare-earth magnet Rare-earth magnets are strong permanent magnets made from alloys of rare-earth elements. Developed in the 1970s and 1980s, rare-earth magnets are the strongest type of permanent magnets made, producing significantly stronger magnetic fields than other types such as ferrite or alnico magnets. The magnetic field typically produced by rare-earth magnets can exceed 1.4 teslas, whereas ferrite or ceramic magnets typically exhibit fields of 0.5 to 1 tesla. There are two types: neodymium magnets and samarium–cobalt magnets. Magnetostrictive rare-earth magnets such as Terfenol-D also have applications, e.g. in loudspeakers. Rare-earth magnets are extremely brittle and also vulnerable to corrosion,