Mouth ulcers: Symptoms, treatment and prevention. Mouth ulcers are sores that appear in the mouth, often on the inside of the cheeks. Mouth ulcers, also known as apthous ulcers, can be painful when eating, drinking or brushing teeth.
Fossils are generally found in sedimentary rock. This occurs because the remains of plants and animals tend to accumulate with the inorganic debris that form such rock. In rare instances, fossils can form in igneous rock, as when volcanic ash or lava congeals around a leaf or insect wing, or fills a footprint.xposed rock is the collector's fruitful ground. Many interesting minerals and fossils can be found on weathered slopes, riverbanks, and cliff faces. Human-made excavations such as road cuts and construction or quarry sites can be excellent sites for mineral hunting.
Fossils are often found in layers of sedimentary rock and along the beds of rivers that flow through them. Other sources of fossils include tar pits, ice, and amber. â¦ Petroleum, coal, and natural gas, which are derived from the accumulated remains of ancient plants and animals, are called fossil fuels.