Comprising three tubogas bracelets set with various cabochon gemstones

METAL: 18k yellow gold
STONES: 9 cabochon gemstones including peridot, tourmaline and amethyst
SIGNATURE: BVLGARI
MARKS: 750, Italian assay marks, numbered
SIZE/DIMENSIONS: 1.0 cm width, flexible size resting at 14.5 cm inner circumference
GROSS WEIGHT: 145.7 grams
Late 20th century

The 'Tubogas' or gas-pipe technique was invented for jewelry during the 1940s, inspired by an ancient Roman technique. The result was a flexible band of gold with polished contours, produced without soldering, and quickly became one of Bulgari's most characteristic and successful designs. The construction of 'Tubogas' requires skilled craftmanship and consists of wrapping two long gold strips with raised edges around a core, often of copper. The edges interlock onto one another and the core is removed. The final product is a springy, flexible band, ready to be decorated with brightly colored gemstones, ancient coins and even watch dials. Bulgari created the 'Tubogas' design in monochromatic variations, as well as contrasting in yellow, pink and white gold.

The use of yellow gold has been a staple for Bulgari since the 1970s, as the firm felt that yellow gold made a jewel more casual and suited for everyday wear. Nicola Bulgari once said "All of it is meant to be worn-not to be kept in a safe deposit box. The jewels complement and are an addition to what the person is wearing." That thought became a tenet for the jewelry firm and since then, the firm has favored the use of yellow gold above all other precious metals.

The use of colorful cabochon gemstones within smooth bezel settings is a staple for Bulgari, which they reintroduced during the late 1960s, after a couple of decades where faceted stones and claw prongs were preferred by jewelers. This style allowed the firm to add volume to their pieces.

This group of three bracelets, being yellow gold, 'Tubogas', and decorated with colored cabochon gemstones, put on full display three important attributes which are iconic for Bulgari.