This is a set of five platonic (perfect) bodies, cube, tetrahedron, icosahedron, octahedron, dodecahedron, really cool cut into rock crystal. These represent the elements earth, fire, water, air and ether. The doctrine of the elements goes back to Plato and Pythagoras. The preparation of it harmonizes the atmosphere in the area. By body size 1-1.5 cm. Beautiful brazilian hand grinding delivered completely in teak wooden box. Geometrical set also called Holy kristallenset. The geometry or geometry (from the Ancient Greek: γεωμετρία, geo- "earth", - metria "measurement") "measuring the earth" is the part of mathematics that deals with the determination of sizes, shapes, relative position of figures and the properties of the space. The Dutch term specific geometry was introduced around 1600 by the Flemish mathematician Simon Stevin. A mathematician, who works in the field of geometry, is called a geometric. Geometry is one of the oldest sciences. Initially started as a body of practical knowledge of lengths, areas and volumes geometry was in the 3rd century BC. provided by Euclid of Alexandria of an axiomatic foundation. All of the initial axioms were formulated in classical Greece (including the postulates of Euclid), where later the entire geometry has evolved from. The axioms were used for the mathematical definition of points, straight lines, curves and surfaces. Euclid's treatment of geometry - Euclidean geometry - nearly 2000 years the standard to which all other work was measured.