Color of entire shell beige iridescent; surface smooth, spire low with about five whorls. Protoconch with hole in adult. Body whorl with very low spiral lines, glossy. Height/width 1.47 on average. Weak carina in lower level of body whorl. Umbilicus almost completely covered by callus, except by narrow lower opening. Orifices in anterior part of mesopodium: 7 on left, 8 on right side. Number of epipodial tentacles: 6 on right side. Rachidian tooth with elongated base, about 1/10 of total radular width, six lateral teeth somewhat similar to rachidian, about 10-12 tall, slender marginal teeth.
Distinctive description:
Shell: Size about 35 mm. Color beige with green tinge. Outline turbiniform; spire height, volume approximately same as body whorl. Protoconch eroded forming small hole communicated with umbilicus. Spire profile forming hemi¬sphere; whorls weakly convex, suture shallow. Sculpture similar to that of G superba; shell surface somewhat glossy; spiral lines weakly visible, about 15 spiral lines on penultimate whorl; axial sculpture almost absent, except some very weak lines in periumbilical area. Callus covering umbilicus almost completely, except for short, narrow lower region , surrounded by inner lip, forming tube communicating with umbilical chamber.

Gaza olivacea is a superbly iridescent Atlantic margaritid ranging from the Caribbean Sea to Rio de Janeiro, Brazil. A very large and attractive Gaza, it is a classic rarity and highly coveted by collectors but its avaiability is very scarce in good condition. A deep-water species, it inhabits sandy to muddy bottoms around -300~700m in depth. The diet or mode of feeding is not well-known for the genus Gaza in general, although sand and mud have been found in the digestive tract which suggest they swallow detritus and digest the organic matter within. Typical shell length around 35mm., extremely large specimens may exceed 45mm. The apex is deciduous and is always missing in adult specimens. It is sometimes confused with the conchologically similar Gaza superba (Dall, 1881) which reaches a similar size, but can be easily distinguished by its taller spire and the umbilicus being nearly completely covered by callus (only half covered in G. superba).

Caribbean Sea to Rio de Janeiro (Brazil)