Zambia is considered the world’s second most important source of emeralds by value (after Colombia). The deposits are located near the Kafubu River in the Ndola Rural Restricted Area. Emeralds have ...

The Karowe Diamond Mine in Botswana, owned and operated by Lucara Diamond Corp., has gained international recognition for producing large, high-quality type IaB or coexistence of IaB with IIa diamonds ...

Raman spectroscopy confirmed the identity of the material as pezzottaite by an intense peak at ~1100 cm –1, which is not present in beryl. Fourier-transform infrared spectroscopy showed features ...

Figure 1. A view of the Lombok farm from the shoreline showing the covered area where the operating and harvesting steps are carried out. Photo by Jeffery Bergman. Cultured pearls are harvested from ...

CARLSBAD, Calif. – June 2, 2025 – Beginning later this year, GIA (the Gemological Institute of America) will start using descriptive terms to characterize the quality of laboratory-grown diamonds and ...

Figure 1. Sapphires from Madagascar: a beautiful 3.29 ct untreated faceted stone and an assortment of rough in the background. Madagascar has produced many high-quality stones in the last few years ...

The micro-world of gems lies at the very core of gemology. Information gathered from observations through the microscope serves as the very foundation for many conclusions drawn on a specimen, ...

Carved single-crystal diamond rings are rare, with few examples to reference (see Spring 2020 Lab Notes, pp. 132–133). But with advancing technology in the laboratory-grown diamond industry, the ...

Figure 1. This necklace of freshwater bead-cultured pearls from China displays strong pinkish purple hues with orient. Photo by Sood Oil (Judy) Chia. Freshwater cultured pearls are known for their ...

At the AGTA show, we spoke with Alex Skachkov of Misfit Diamonds (Vancouver, Canada) about some of their unusual diamonds (figure 1). When asked what was popular, he showed us their aptly named “salt ...

Chemical vapor deposition (CVD) growth technology has advanced significantly over the last two decades. In this study, we report on the largest CVD gem diamond GIA has encountered, recently tested in ...

In November 2022, a parcel of 24 approximately 0.5–1.2 ct spinel crystals, described as cobalt-diffused, were obtained directly from a treater by the research team at GIA in Bangkok. Of these, seven ...