Alexander II of Russia

ALEXANDRITE. A variety of chrysoberyl, originally found in the schists of the Ural Mountains. It absorbs yellow and blue light rays to such an extent dial it appears emerald green by daylight but columbine-red by artificial light. It is used as a gem, and was named in honor of Czar Alexander II of Russia See also Chrysoberyl. 

A gem closely related to ruby and emerald is alexandrite, named after Alexander II of Russia. This gem is based on the mineral chrysoberyl, a beryllium aluminate with the empirical formula BeO AI2O3 in which approximately 1% of the Al3+ ions are replaced by Cr3+ ions. In the chrysoberyl environment Cr3+ absorbs strongly in the yellow region of the spectrum. Alexandrite has the interesting property of changing colors depend-... 

As Amy Lawrence researched the Romanov execution, she found the following information about one of the earlier Romanov czars. To practice some of the skills you ve learned so far, read the following passage on Alexander II of Russia (1855-1881) and do the tasks that are listed after it. 

In more recent times, following an initiative by Czar Alexander II of Russia, the delegates of 15 European States met in Brussels on 27 July 1874. The conference adopted the Brussels Declaration of 1874 which included the following provision Art. 13. According to this principle are especially forbidden (a) Employment of poison or poisoned weapons... (e) The employment of arms, projectiles or material calculated to cause unnecessary suffering . However, this declaration was not accepted by all of the governments as a binding convention and it was therefore not ratified. 

A gem closely related to ruby and emerald is alexandrite, named after Alexander II of Russia. 

The use of the chlorate and sugar or nitrobenzene mixtures for purposes of political assassination and sabotage as in partisan mixtures, and their modifications to produce delayed reaction mixtures such as Molotov Cocktails are described by Stettbacher. He attributes the death of Tsar Alexander II of Russia in 1881 and the Irish baggage explosions in London in 1938 to bombs containing such ingredients. The author also quotes in this book articles by himself about chemical ignition... 

In this endeavor the original author of Handbook-I has been joined by Alexander Pozharskii of the University of Rostov, Russia. We have adopted for Handbook-II (for the most part) the arrangement and classification of Handbook-I. However, a large amount of new material has been added, most of which has been taken from the 10 volumes of CHEC-II. In many instances we have utilized pieces of actual text and structural schemes directly from CHEC-II. Because of the close relationship to CHEC and to CHEC-II, the Foreword, Introduction to CHEC-II and Short Contents of both CHEC and CHEC-II are reprinted as part of the Part I Preliminaries of Handbook-II. Just as for Handbook-I, the organization of Handbook-II follows that of the CHEC and CHEC-II rather closely except in the case of ring synthesis, and Chapter 1.3 of the Handbook describes these divergencies. 

Beryllium aluminum silicate, just discussed, is not the only beryllium mineral to occur as precious stones. Chrysoberyl BeAl O with a small amount of iron is also used as a gem. It is usually yeUow, pale green or brown. A transparent variety of chrysoberyl is alexandrite, named after Alexander II, tsar of Russia. It has a green color in daylight but is red in artificial light. 

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