Brass is a homogeneous mixture (solid solution) of copper and zinc. Again each metal by itself is a pure substance. Only when they are mixed are they a homogeneous mixture (or solid solution). Heterogeneous Mixtures Heterogeneous mixtures are not uniformly mixed on an atomic or molecular level.
Penrose is one of the small villages in the Southern Highlands, located between Bundanoon and Marulan.
Penrose tiling. A Penrose tiling is an example of non-periodic tiling generated by an aperiodic set of prototiles. Penrose tilings are named after mathematician and physicist Roger Penrose, who investigated these sets in the 1970s. The aperiodicity of prototiles implies that a shifted copy of a tiling will never match the original.