"Chasing" The Planets
Authors: Heward Anita 
Published: October 2020

I present a series of works inspired by planetary bodies, created from copper and pewter sheet that has been worked through chasing and repouss&#233; techniques to describe topographical relief, and with patinas and oxidation applied to add colour and contrast.In this oral presentation, I propose to show some of the techniques and effects used in creating the works, discuss how the project has come about through a combination of personal and professional inspirations, and consider how a combination of ancient artform and kitchen chemistry can be used to look at cutting-edge planetary mission data in new ways. &#160;IntroductionChasing (working metal from the front) and repouss&#233; (working metal from the back) are ancient decorative techniques that date back to at least 1600 BC[i]. When used on thin, soft, metal sheeting, detailed relief work can be achieved with a set of simple tools without need for annealing or pitch backing.Since 2014, I have used copper and pewter sheet to create a number of works related to planetary bodies, including the Moon, terrestrial planets and the moons of Jupiter. As well as making wall-mounted panels, I have experimented with suspending double-sided 2D representations to make mobiles and decorations.Pewter is a soft metal, composed mainly of tin, that can be worked easily from either side to create detailed relief designs. Application of an oxidising solution, via immersion or using a soft cloth, will achieve a range of tones from dull grey to black. Bright, silver-coloured highlights can be achieved through polishing.Copper is an extremely versatile material. Its natural bright orange colour lends itself to the representation of Mars or Venus. However, heating with a blow-torch or the application of patinas can result in a wide range of colours, from pinks and yellows through to deep blues and greens [Fig. 3].I use lead-free pewter sheet (95% Tin, 4% Antimony &amp; 1% Copper) of 0.15mm thickness and 50cm width, and copper sheet of 0.127mm thickness and 30cm width. The sheets come in rolls of up to 2-3.5+ metres, enabling the creation of relatively large-scale installations. Application of a thin layer of lacquer to finished works prevents patinas from flaking and prevents polished metal from tarnishing.Description of worksPhases of the MoonI have created a number of works in pewter, ranging from around 10 cm to 1.8 metres, representing the phases of the Moon [Fig. 1]. Topography is not to scale but uses the LROC GLD100 model as a guide, as well as a range of visual images taken by ground-based observers. In interpreting the essentially black-and-white images of the Moon through the medium of oxidation of pewter, it can be a challenge to understand the respective contributions of the geology on the reflectance of the surface, and the angle of illumination in producing light and dark areas. This is a particularly important consideration when working at larger scales.Terrestrial planetsI have created sets of individual panels representing the four terrestrial planets [Fig. 2], with Mercury and the Earth in pewter and Venus and Mars in copper. Topographical data from Messenger (Mercury), Magellan (Venus), NOAA ETOPO1 (Earth), MOLA/Mars Global Surveyor (Mars) has been used for reference in creating relief features.Earth / exoplanetsHousehold ingredients and cleaning materials (salt, vinegar, ammonia, sawdust) can be used to create copper patinas ranging from a dull olive green to bright turquoise and deep blue, which can give the impression of vegetation or oceans in terrestrial landscapes [Fig. 4].Outer planetary systems.The range of colours produced by oxidising copper during heat treatment lends itself well to the vivid colours of Jupiter&#8217;s moon, Io. The ultramarine and turquoise colours of clouds on Neptune and Uranus may be represented through copper patinas. Over the summer, I intend to work on a series related to outer planets and their moons. My presentation will detail work in progress as well as the final versions.

[i] Metalworking through History: An Encyclopedia, By Ana M. Lopez, Pub: ABC-CLIO, 2009. pp47-48