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.
Architecture describes what is in your system. When you have determined your context, you have determined a boundary that describes what is in and what is out of your system (which might be someone else's subsystem). Architecture describes the part that is in. An architecture is an abstract depiction of your system. The information in an architecture is the most abstract and yet meaningful depiction of that aspect of the system. Given your architectural specification, there should not be a need for a more abstract description. That is not to say that all aspects of architecture are abstract, nor is it to say that there is an abstraction threshold that needs to be exceeded before a piece of design information can be considered architectural.