Some 150 years ago Russian mineralogist, Member of the St. Petersburg Academy of Sciences, Nikolai Koksharov, made an interesting discovery while visiting a small village, Slyudyanka, on the shore of Lake Baikal in Siberia. What he found was a mineral of an unusual salad color which belonged to the pyroxene group. He named his find "lavrovite" in honor of the then President of the All- Russia Imperial Society of Mineralogy Lavrov 20 years later the find was studied for the first time by a team of German chemists. During the more than one hundred years since Koksharov's discovery none of the mineralogists who studied the mineral has confirmed the "vanadium-related" color of lavrovite, although the fact that it contains vanadium was common knowledge among experts. Quite recently a team of German chemists have published an article under an intriguing title questioning the "authenticity" of lavrovite. This was followed by a report on a discredit of the very name "lavrovite".

The controversy has attracted the attention of Dr. Leonid Reznitsky, a research scientist of the Institute of the Earth Crust of the Siberian Branch of the Russian Academy of Sciences (Irkutsk). He and his team visited the site of the original discovery - the village of Slyudyanka in Siberia. What they found there was not only the mineral in question, but five new ones as well.

The first of these turned out to be a very unusual one: it belonged to the spinel group which contains zink, chromium and sulphur - a very rare group earlier encountered only in meteorites. The mineral was given the name of "kalininite" in honor of a scholar who studied the Pribaikalye (near Baikal) region - Professor Pyotr Kali-nin of the Moscow Institute of Geological Prospecting.

The second mineral in the group - and contrary to the claims of the German scientists - was vanadium pyroxene. Dr. Reznitsky called it "nataliite" after a prominent Siberian geologist Dr. Na-talya Frolova.

The third of the newly discovered mineral also features an unusual composition - some of its chromium is replaced with antimony (such compound was found for the first time). It was given the name of "florensovite" in honor of Nikolai Florensov - the founder of the Institute of the Earth Crust of the Siberian Branch of the Russian Academy of Sciences, Corresponding Member of the Academy

The fourth and fifth of the newly discovered minerals can be described as varieties of vanadium spinel and rare chromium mica. The latter is an analog ofmuscovite mica in which aluminum is replaced with chromium that gives the mineral its beautiful bright-emerald color. And it was called "chromphillite".

Dr. Reznitsky's fellow partner in nearly all of the discoveries is Corresponding Member of the Russian Academy Yevgeny Sklyarov - Director of the Institute of the Earth Crust of the Siberian Branch of the Russian Academy

Over the past few decades the Institute's scientists have discovered more than 20 new minerals. In addition to those mentioned above, seven were discovered by a leading researcher of the same Institute Alexander K-onev, another five (including charoite-a fine stone of a violet color) by Vera Rogova, and still another seven-by researchers from the Vinogradov Institute of Geochemistry- Vladimir Ivanov, Yevgeny Vforobyev, and Nikolai Vladykin. And the search continues now, adding to Slyudyanka's unique record of more than 200 years as a "natural" miner-alogical museum.

Nauka v Sibiri (Science in Siberia), 1999

Prepared by Emma SOLOMATINA

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