Unique three-dimensional patterns of black opals and their value indicators on the world market
| S. Shevchenko Dnipro University of Technology |
| Language: Ukrainian |
| Precious and Decorative Stones. No.3-4 (117-118), 2024: 9–20 |
| Abstract The task of this work is to establish regularities between the type and complexity of patterns (volumetric texture patterns) of black Australian opals and their market value. The research methodology included the analysis of different types of black opal patterns, their interpretation for the Ukrainian-speaking reader through sets of recognizable artistic images, determination of the specific value of the corresponding samples of black opals in relation to their weight, as well as a schematic representation of value dependence on the type and complexity of the three-dimensional pattern. As a result, the article reviews the most common names of varieties of black opals, classifies their textural patterns by complexity, namely by the presence and sizes of point, linear, regular and irregular two-dimensional geometric figures; by associative features, an artistic interpretation of the images that an observer can see in opal samples is provided, and it is also demonstrated that the market value of black opals starts from $100 to $2000/ct for opals with the simplest (indistinct) pattern, increasing for opals with linear elements ( from $3,000 to $5,000/ct), opals with irregular two-dimensional elements ($5,000 to $20,000/ct), and reaching the highest figures for harlequin opals with clear geometric shapes (up to $50,000/ct). Further research involves the creation of a database of three-dimensional patterns of black opals in the form of a video library, as well as the development of a methodology for forecasting the market value of Australian black opals, taking into account the main quality indicators. The practical significance of this work lies in the possibility of using the given patterns for potential consumers to avoid situations related to incorrect or unethical behaviour of black opal sellers. |
| Keywords: black opals, patterns, artistic images, value. |
| References |
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