From about 1450 output included goblets, cups, and
bowls of dark red, green, and blue glass, modeled on
shapes used by contemporary metalworkers. These were
painted in enamels in contrasting colors with historical
and mythological scenes and on betrothal goblets medal-
lion portraits of bride and groom. This style was later su-
perseded by painted geometric and fish-scale decoration,
with imitations of inset jewels.
Toward the end of the 15th century a clear colorless
glass called cristallo was developed. Its great ductility and
rapid cooling allowed glass blowers to make thin-walled
vessels, tazzas, and other items of austere, unadorned
beauty. Gradually this cristallo ware became more orna-
mented, with fantastic applied winged shapes and han-
dles. Admiration for antique Roman glass led to the
revival of millefiori and mosaic glass, and to the imitation
of such natural stones as aventurine and chalcedony. Sim-
ilarly the Roman use of rope-like decoration inspired the
well-known latticino ware with interlaced white threads in
the glass. Another widely practiced technique produced
cracked-ice glass, particularly effective when used for
water jugs and bowls.
Eventually migrant workers from Genoa, not bound
to secrecy, enabled many northern European centers to
produce imitative glassware in what was called “façon de
Venise.” The technique of making Venetian crystal was
brought to England early in Elizabeth I’s reign by glass-
makers from Lorraine and Venice; in 1575 she awarded
the Venetian glassmaker Giacomo Verzelini (1522–1606)
a monopoly for this product. In Germany there was a dif-
ferent indigenous glass-making tradition, with beakers
and stemmed glasses, almost always in green glass, often
with prunt decoration. The classic German wine glass, the
roemer, was an early 16th-century development. Kaspar
Lehmann (1563–1622), jewel-cutter to Emperor Rudolf
II, pioneered the technique of decorative glass cutting,
for which he obtained a monopoly in 1609 and which
he passed on to his pupil Georg Schwanhardt. This her-
alded the predominance of Bohemian glass in the post-
Renaissance period.
Fine glass vessels such as the Venetian and Bohemian
wares were always goods for the luxury end of the market.
A major difference between the glass factories of the
Mediterranean area and northern Europe was that the for-
mer used soda-ash obtained from various maritime plants,
which was capable of yielding good-quality crystal, while
the latter had to rely on potash from sundry kinds of veg-
etation, with more variable results. Less glamorous glass
manufactories, capable of turning out utilitarian items for
local use, existed in Europe throughout the Middle Ages
wherever a supply of all the necessary raw materials was
readily to hand: ashes (preferably of beechwood, but also
of ferns or bracken, which gave rise to the French name
verre de fougère); sand of a suitable composition; clay ca-
pable of being made into crucibles that could withstand
temperatures in excess of 1200°Celsius; and an abun-
dance of wood to fuel the furnaces. A manuscript of Man-
deville’s Travels in the British Library dated c. 1420 and
probably from Bohemia contains a miniature showing var-
ious stages of glass manufacture from digging the sand to
removing the finished vessels from the furnace. In Eng-
land the Weald of Surrey and Sussex in the southeast of
the country was probably the major center for the craft,
but Cheshire and Staffordshire too had the necessary com-
bination of materials to support a glass-making industry.
The characteristics of the sand used, which usually con-
tained small percentages of iron oxide, meant that most
English medieval glass is either green or tinged with
green. Flanders, Normandy, and the Rhineland were all
significant northern European glass-making areas. Other
items made in the humbler workshops were hanging
lamps, flasks, vessels and tubes for distilling, urinals, and
solid balls of glass used for smoothing materials in various
industrial activities.
Until the 16th century, when specialization became
common, the manufacture of glass vessels and other
pieces was normally only one aspect of a workshop’s out-
put, and in many cases the making of glass for windows
was the more important activity. Colored glass for stained-
glass windows was considerably more expensive than
white (clear) as the minerals necessary for making it often
had to be imported from afar: cobalt for blue may have
come from the Near East in the form of a diluted colorant
called “zaffre.” Copper was needed for red. The tech-
niques for obtaining the rich colors associated with me-
dieval church windows were already understood at the
beginning of the period, and the main technological de-
velopment of the later Middle Ages and Renaissance was
the ability to produced larger panels of glass. The main
medieval process (the “crown” method), associated par-
ticularly with the glass makers of Normandy, produced a
circular disk from which the glaziers cut window panes.
The more complicated “muff” technique was refined by
French Huguenot makers in Lorraine who took their skill
with them to other parts of Europe when they became
refugees in the late 1560s.
Further reading: Patrick McCray, Glassmaking in Re-
naissance Venice: The Fragile Craft (Aldershot, U.K.: Ash-
gate, 1999).Goes, Hugo van der (c. 1440–1482) Flemish artist
Probably born at Ghent, Hugo van der Goes was accepted
as a master in the painters’ guild there in 1467, although
few other details of his early life are known. He executed
decorations for such public events as the marriage of
CHARLES THE BOLDand Margaret of York (1468) and a
number of paintings reflecting the influence of Jan van
EYCKand Rogier van der WEYDEN, notably a diptych begun
in 1467. Having been made a dean of the painters’ guild in
1474, Hugo entered the Augustinian monastery of the Red221166 GGooeess,, HHuuggoo vvaann ddeerr