A mineral, by definition, is. . . 1  Inorganic, which means that it is not made by a living organism. 2  A solid. 3  Has a regular crystal structure. 4  Made by nature which means minerals are not made, directly or indirectly, from human activity. 5  Has a predictable chemical formula. A solid. 2  There is one unusual exception. 3  Native mercury is a mineral and is the only metal that is a liquid at normal temperatures. 4  Has a regular crystal structure.
Image:Cultural Heritage Agency of the Netherlands 20309407 - RCE. An A-frame house is an architectural house style featuring steeply-angled sides (roofline) that usually begin at or near the foundation line, and meet at the top in the shape of the letter A. An A-frame ceiling can be open to the top rafters.
Modern and contemporary styles tend to get confused. Modern architecture refers to design inspired by the historical art movement of modernism. Most classic examples of modern architecture are more than 50 years old, which makes it a little easier to tell a modern-style home from a contemporary-style home. Open living spaces, clean, geometric lines and function-over-form are key elements of the style.