GianCarlo Montebello's interest in interior decoration dates back to the early 1960s where his Milanese exhibition space allowed him to meet a number of key architects. Later, his attention shifted to other fields and he opened a goldsmith workshop, GEM, dedicated to working with and producing for artists.

His encounters with photographer Ugo Mulas and Man Ray substantially influenced and helped guide his life for many years. In addition, numerous collaborations with artists, galleries and collectors, as well as a theft in which all his work with artists was stolen, finally prompted him to make jewellery of his own.

From 1983, he collaborated with jeweller Enrico Trizio, designed silverware for a Japanese company, participated in exhibitions and lectured at Milan's European Institute of Design. In 1987 he concentrated mainly on private commissions and in the mid-1990s he completed the cycle that had begun in 1983 of his Ornamenti di Bradamente.

He was also invited to present the productions of Gem Montebello at the Guggenheim Museum in New York City (1993-1994). This work was again included in the exhibition New Times, New Thinking: Jewellery in Europe and America (1995-1996). Various jewels by GEM and Montebello have also been featured in the volume Fifty Years of Italian Artists, Jewels. Montebello's research finds its principal guidelines in the study of the characteristics of various materials, especially their compatibility with certain forms rather than with others.