However, even this small critical mass greatly exceeds the total amount of einsteinium isolated thus far, especially of the rare 254Es isotope.
Nevertheless, the slightly shorter-lived 256Md (half-life 1.27 hours) is more often used in chemical experimentation because it can be produced in larger quantities from alpha particle irradiation of einsteinium.
The most important and most stable isotopes are in the range from 254Md to 258Md and are produced through bombardment of einsteinium isotopes with alpha particles: einsteinium-253, -254, and -255 can all be used.
In a "typical processing campaign" at Oak Ridge, tens of grams of curium are irradiated to produce decigram quantities of californium, milligram quantities of berkelium and einsteinium and picogram quantities of fermium.
Despite the short half-lives and scarcity of einsteinium isotopes, einsteinium metal has been prepared in milligram (10−3 gram) amounts.
The isotope of einsteinium with the longest half life, einsteinium-252 (half life 471.7 days) would be more suitable for investigation of physical properties, but it has proven far more difficult to produce and is available only in minute quantities, and not in bulk.
Separation procedure of einsteinium depends on the synthesis method.
