by Maria SAPRYKINA, Science in Russia observer

This article acquaints our readers with a remarkable scientist Tatyana Zdorik, Cand. Sc. (Geol. & Mineral.), who has been actively popularizing mineralogical science. In addition, she is a translator and author of numerous scientific textbooks and a series of articles on mineralogy. She told our correspondent Maria Saprykina about her scientific studies, creative activities and main achievement-description of a new mineral-calcircite.

-- Tatyana Borisovna, please, tell us what was the reason to focus your research efforts on minerals?

-- In some way, I was closely connected with mineralogy and geology practically right from my birth. My parents were geologists. So, 1 chose a profession and took a decision to enter the MSU Department of Geology under the influence of my relatives and the atmosphere of love and interest in science reigning in my family. In 1955, I finished my studies at the chair of petrography and soon after that was employed at the Department of Rare Metals of the All-Union Institute of Mineral Resources in Moscow, at that time the first national institute specializing in ores and raw materials. This research institution was established in 1923 by the USSR Ministry of Geology as the Institute of Applied Mineralogy on the basis of the Institute of Petrography "Litogea". It got its contemporary name in 1935. From that time and till our days, main efforts of the institute have been concentrated on research, expansion, and improvement of ore and raw material

base of ferrous and a number of branches of non-ferrous metallurgy. Today, the institute keeps developing scientific fundamentals of geological forecasting, exploration, and integrated valuation of ore fields, problems of genetic and applied mineralogy, analysis and technology of minerals.

-- What were your specific tasks as a research assistant of the Department of Rare Metals?

-- That time (I mean early 1960s) I was entrusted to explore a new type of deposits--carbonatites (in particular, tantalum and niobium deposits). Tantalum (in pure form) is a bright silver-white metal with a high melting temperature. It is a hard metal characterized by high plasticity like gold and paramagnetic properties. In terms of chemical resistance to reagents, tantalum is very close to glass; it is not soluble in acids and their mixtures. It dissolves only in the mixture of hydrofluoric and nitric acids. Niobium is also a bright silver-grey metal. Chemically it is fairly stable. It is always accompanied by tantalum. Similar chemical properties of niobium and tantalum precondition their joint presence in the same minerals and participation in common geological processes. Niobium is even able to replace titanium in a number of titaniferous minerals. In nature, niobium can be found in two forms: difuse (in rock-forming and accessory minerals of magmatic rocks) and mineral. In general, we are aware of over 100 niobium-containing minerals. It is mainly applied in rocket engineering, aircraft and space technology, radio engineering electronics, chemical instrument-making, and atomic power engineering. Production and use of niobium has been rapidly increasing, which is explained by an efficient combination of its properties such as refractoriness, small section of thermal neutron capture, capacity to form heatproof, superconductive and other alloys, corrosion resistance, low electron output function, easy processing by in-cold pressure, and weldability. By the way, niobium and tantalum are used to manufacture high specific volume electrolytic condensers (however, tantalum condensers are of higher quality).

Thus, the last 5 field seasons (3-4 months a year) I worked in the south-eastern part of Yakutia on the Mountain Lake* deposit (mountain-mass). This fact has preconditioned my future geological discovery.

-- Could you explain in more detail what carbonatites are and what you found out while studying this type of minerals?

-- To begin with, I'd like to say that carbonatites are a type of rare metal deposits. By now, scientists established a stage character of mineral formation typical of it: during the first stage, coarse-grained calcites with inclusions of titanium and zirconium minerals are formed: during the second stage--middle-grained calcites with supplementary minerals of titanium, uranium and thorium; during the third stage--fine-grained calcite and dolomite aggregate with niobium mineralization: during the fourth stage--fine-grained masses composed of dolomite and ankerite and inclusions of rare-earth carbonates. Carbonatites have a massive, banded, knotty, and plicated (composed of minor folds) texture, and a varied grain structure. In other words, these minerals are deep mantle rocks formed under the continents. Besides, alkali carbonate magma

*The areas of rare metal carbonatites in the southern and south-eastern part of Yakutia (Mountain Lake, Arbagastakh, and other massifs) are main potential sources of niobium, tantalum and rare earths.--Ed.

absorbs such elements as strontium, barium, rare earths, thorium, uranium, phosphorus, zirconium, titanium, niobium, and tantalum. Mobile complex compounds of these elements are preserved in a highly alkaline medium of carbonatites during their lifting to the upper horizons of the crust and form different minerals--high grade ores of iron, phosphorus, copper, tantalum and niobium, rare earths, zirconium, etc.

As for my direct work duties, in addition to annual reports on long-term expeditions to carbonatite deposits, I collected a lot of information for my scientific work and published results of these studies. Thoroughly studying the rocks, I found a new mineral and gave it a sounding name--calcircite, proceeding from its chemical composition, and described it in detail in my works. But 1 realized that purely scientific works are not easy to understand for the public at large (and sometimes even totally incomprehensible!), and was eager to make both professional scientists and ordinary people, interested in mineralogy and far from the world of science, get acquainted with my work and discoveries.

I was speculating on a number of options to make my great ambition come true, and, as a professional geologist, took the following decision: to tell about my discoveries to the public at large in the simplest and most comprehensive form possible. That was a real success! 1 was a co-author of numerous popular scientific books on minerals, including books for school children

("Hello, Mineral!", "Open Slightly the Malachite Box", "Stone Giving Birth to Metal", etc.). In addition, if we have touched my research works, it is necessary to point out that I am one of the four authors (my coauthors were mineralogists V. Matias, I. Timofeev, and L. Feldman) of a volumetric scientific paper Minerals and Rocks of the USSR (1970). This illustrated reference book is a complete guide dedicated to minerals and rocks widespread in the territory of Russia. It is also meant for ordinary tourists, regional ethnographers, members of geological expeditions, professional geologists, and, in general, for all inquisitive people interested in and enjoying the mysterious world of minerals.

-- Tatyana Borisovna, the books you named are still popular among various categories of readers. I would like to thank you for the interesting account and ask the last question: what are your future plans?

-- I hope that in the future my scientific works and articles will encourage young scientists to get seriously engaged in the further development of mineralogical knowledge. The mysterious world of minerals still keeps secrets to be solved.

You have asked me about my recent achievements... For the last few years, I am carried away by translation of works in geology and mineralogy. This is one more sphere of my professional interests. I have translated a number of factual books on minerals from German: Herbert Bank In the World of Semi-Precious Stones (1979), Verner Gilde The Mirror World (1979), Environmental Essays on Nature and Man (1982), etc.

Best wishes to Tatyana Borisovna, new successes in her creative work, good health and long life.