Architectonic jewellery is a subset of Constructivist studio jewellery that makes use of architectural forms and ideas in the much smaller-scale format of jewellery. Some of the defining elements of architectonic jewellery are linearity, inclusion of geometric elements, undisguised structural elements, and use of varying depth to convey a sense of design in three dimensions rather than only two. Certain architectonic pieces include moving parts, which enables "extending or reconfiguring" the pieces by the wearer. Architectonic jewellery often incorporates materials more typically used in engineering such as stainless steel and niobium, reinforcing the association with architecture.