The use of silicon carbide (synthetic moissanite) led to the development of electrical conductivity testers of similar appearance, but which worked on different physical properties—electrical rather than thermal.
Featured ArticlesThe bangle is the most popular jade jewel, but it is also the most complex to select. Next to all quality parameters, personal preferences, and budget, choosing the right size is of utmost importance. And when it comes to green and purple jadeite, perfect bangles are, as one would say, unheard of. Table 1 shows approximate retail values that currently apply for inferior to exceptional quality jade.
Featured ArticlesThis is the first comprehensive researched based study in more than a decade, comparing jewelry store margins using a broad spectrum of the industry. Markups are a key component to valuation assignments and understanding these margins is critical for appraisers to use in valuations.
Featured ArticlesThroughout history, Afghanistan gemstones have been of great value and steadily increasing in value. Today, mostly private families and residents operate mining and it is their main source of income. Over the years, organizations have worked together to develop the legal trade from this country.
Featured ArticlesThe mineral collection of the Mineralogical and Geological Museum at Harvard University (MGMH) has played a significant role in the advancement of the science of mineralogy.
Featured ArticlesDetermining pricing for treated diamonds can be a great challenge. The focus here is on the history and pricing trends of modern-day diamond treatments. Four are in this group including laser drilling, clarity enhancement, high pressure high temperature (HPHT), and irradiation.
Featured ArticlesFor our series on innovators in jewelry design, this month we are focusing on multiple AGTA award winning artist, gem cutter, metalsmith, and gemologist Derek Katzenbach owner of Katzenbach Designs. Located in Maine, it came as no surprise that Derek has a special passion for working natural Maine tour- maline.
Featured ArticlesIn light of the recent announcement that the Gübelin Gem Lab would introduce a rating system for gemstones, which is admittedly influenced by the process in use for wine, it seems appropriate to examine the potential implications for our industry, but from the context of the wine industry, where the pros and cons of such systems are known.
Featured ArticlesCorals used in jewellery are commonly referred to as precious corals.
Featured ArticlesEstablishing value of a gemstone starts with correct identification; second logical step is grading but doesn’t end there.
Featured Articles