Established in 1931, the Gemological Institute of America (GIA) is the world’s foremost authority on diamonds, colored stones, and pearls. A public benefit, nonprofit institute, GIA is the leading ...

Over the past several years, diamond simulants have entered the market that consisted of colorless cubic zirconia reportedly coated with a thin layer (e.g., represented to be 30–50 nm) of ...

Figure 1. These 20 completely non-nacreous pen pearls, from the group of 22 samples in this study, are set against a pen shell displaying both nacreous (left) and non-nacreous areas (right). Photo by ...

During the last 20 years, Australia has assumed a major role in the production of blue sapphire. Most of the gem material comes from alluvial deposits in the Anakie (central Queensland) and New ...

If you were born in the month of June, you are lucky enough to have three birthstones to call your own. June is one of only three months (the others are August and December) that has three birthstones ...

Some natural opals, mostly from Ethiopia, show a macroscopic finger-like structure called a digit pattern. This pattern consists of vertical columns that are more or less parallel, separated by a ...

As a consumer, you will regularly encounter in the marketplace gems that have been treated to change their appearance. A topic that often comes up is whether a particular gemstone is or isn’t treated.

The gemological and spectroscopic properties of 52 colorless to fancy light-colored HPHT synthetic diamonds (40 of them colorless or near-colorless) produced by AOTC using either toroid- or BARS-press ...

GIAに宝石をご提出いただく場合は、ラボサービスアカウントを開設していただく必要があります。アカウントはすべてオンラインで簡単に開設していただけます。 アカウントを開設するためには以下が必要となります。 ビジネスを代表してアカウントを ...

The majority of saltwater and freshwater pearls bought and sold in the global jewelry markets are “whole pearls,” sometimes referred to as “cyst pearls” (CIBJO, 2017). These pearls form within the ...

2.61 total carat weight of brown diamonds, 17.83 total carat weight of diamonds, 18K yellow gold, platinum and Native American pottery were used in this pendant (8 cm across), known as "The Acoma ...

同行审查的季刊《宝石及宝石学》(Gems & Gemology) 已对宝石学科学产生了深远影响。 八十年来，其报告一直为科学家和研究人员提供资料，教育了一代代的宝石和珠宝专业人士。 我们请该杂志的编辑和主要撰稿人审查该杂志的大量作品，并选出他们认为特别重要 ...