ANALYSIS OF ELECTROFORMED GLASS SURFACES BY ELECTRON MICROSCOPY: SEM STUDY OF COPPER-COATED ARTISTIC GLASS

This study analyses the surface of copper-coated
artistic glass produced by electroforming technique,
using scanning electron microscopy (SEM) as the
primary characterisation tool. Non-conductive glass

substrates were rendered conductive with a powdered-
graphite layer and then coated with copper in an acidic

copper-sulphate bath. Two families of experiments
were carried out on 3 × 3 cm × 5 mm tiles: a voltage
series (0.1, 0.2 and 0.3 V) and a current series (0.1, 0.2
and 0.3 A), each at holding times of 25, 50 and 100
minutes, with all other parameters held constant. SEM
imaging of the graphite layer, of every deposition
condition, and of the deposit in profile reveals a
systematic evolution of the copper morphology. At
low-to-moderate driving force (0.1–0.2 V, 0.1 A) with
sufficient time the deposit consists of fine, coalesced,
comparatively smooth grains that form bright,
homogeneous films; at 0.2 V it is densest and most
uniform. As the driving force increases (0.3 V and,
most markedly, 0.2–0.3 A) the copper grows as coarse
three-dimensional botryoidal (cauliflower-like)

spherulites separated by deep crevices, a rough, light-
scattering morphology that corresponds to the dark

and eventually black surfaces observed
macroscopically; a profile view confirms the
columnar, mounded growth habit at high current. A
distinctive methodological feature of the work is the
use of powdered graphite, rather than silver or liquid
copper pastes, as the conductivity layer. The SEM
evidence provides a micro-structural explanation for
the macroscopic colour and texture and yields a
reproducible parameter map that allows the artist to
steer the surface from bright metallic to dark patinated
through voltage or current and time alone.