These rings allegorize transitions between different states in a general sense. The ring band shows a gradual transition from one type of profile to another one (e.g. from triangular to square). However, in one position, where the two profiles meet, the change is abrupt. Thus, the ring profile undergoes a metamorphosis. The rings were produced by sand casting: I first made a wax model of each ring, then I produced a mould of it by imprinting it in (sticky) sand, and finally the hollow was filled with molten silver. I am afraid the descriptions are a bit technical...
Vierkant versus Vierkant
(rectangle vs. rhomb) Ring (one of a kind) Silver 925, sand cast, diameter 27 mm A rectangular profile transforms to a rhombic profile (or vice versa). The outer and the inner faces of the rectangular profile taper to two lines forming the outer and the inner edge of the rhombic profile. In parallel, the lateral faces of the rectangular profile develop increasingly stronger ridges, which finally become the lateral edges of the rhombic profile.
Dreikant versus Vierkant I
(triangle vs. square, version I) Ring Silver 925, sand cast, diameter 26 mm A trianglular profile transforms to a square profile (or vice versa). There are two possibilities of continuous transformation: In this version, the outer face of the square profile tapers to a line, forming the vertex of the triangular profile, while the two sides of the ring form circular ramps.
Dreikant versus Vierkant II
(trangle vs. square, version II) Ring Silver 925, sand cast, diameter 26 mm A triangular profile transforms to a square profile (or vice versa). There are two possibilities of continuous transformation: in this version, the outer face of the square profile develops a increasingly steeper ridge, which finally becomes the vertex of the triangular profile. The two sides of the ring exhibit elegant helical faces.
Ring Silver 925, sand cast, diameter 26 mm The two base profiles are mutually mirror-symmetrical, right-angle triangles. The outer edge of the triangle profile describes a helix, transforming one profile to the other.
Ring Silver 925, sand cast, diameter 25 mm Seen from the side, this ring looks exactly the same as "Dreikant versus Vierkant II" because it uses the same type of transformation. However, here the transformations run antidromically on the two sides of the ring. This produces a pretty cross motif at the position of abrupt transition.
(hidden cross) Ring (one of a kind) Silver 925, sand cast, diameter 26 mm This ring uses the same antidromic transformation as the ring "Crux", but it runs somewhat hidden on the inside of the ring.
Quadratur des Kreises
(squaring the circle) Ring (one of a kind) Silver 925, sandcast, diameter ca. 20 mm In this ring, the profile of the ring band remains constant, forming a flat rectangle, while the overall shape of the ring transforms from a square to a circle (or vice versa). Circle and square enclose the same areas.