osmium-187

isotope

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July 2, 2026

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Osmium-187 is a naturally occurring isotope of the element osmium (Os). Osmium is a dense, hard, and brittle metal belonging to the platinum group. Natural osmium is a mixture of seven stable isotopes, with osmium-187 comprising about 1.96 percent of the total.1

A significant application of osmium-187 is in rhenium-osmium dating, a method used to determine the age of minerals like molybdenite. This technique relies on the radioactive decay of rhenium-187 into osmium-187. Because molybdenite has a high ratio of rhenium to osmium, and its osmium is almost entirely radiogenic osmium-187, it allows scientists to date ores ranging from 38 million to 3 billion years old.2

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osmium
59 percent), osmium-187 (1.96 percent), osmium-188 (13.24 percent), osmium-189 (16.15 percent), osmium-190 (26.26 percent), and osmium-192 (40.78 percent).
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59 percent), osmium-187 (1.96 percent), osmium-188 (13.24 percent), osmium-189 (16.15 percent), osmium-190 (26.26 percent), and osmium-192 (40.78 percent).
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spectroscopy
Thermal atomization
…isotope rhenium-187 (¹⁸⁷Re) decays to osmium-187 (¹⁸⁷Os) having a half-life of 43 billion years; hence, the Re-Os system can be used to determine when geologic materials were solidified in Earth.
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…isotope rhenium-187 (¹⁸⁷Re) decays to osmium-187 (¹⁸⁷Os) having a half-life of 43 billion years; hence, the Re-Os system can be used to determine when geologic materials were solidified in Earth.
Read More