Preparation in the Earth Sciences

Samples of interest to the Earth Sciences tend to be highly stable but insulating in nature. In addition, these rarely exhibit smooth fiat surfaces unless polished. Samples may also be small in size, i.e. may take the form of millimeter- to micron-sized grains. As all of the above can pose problems in carrying out the highly precise and distortion-free SIMS measurements, specific sample preparation procedures have been developed. 

In the case of small grains, sample preparation generally takes the form of  

Preparing a mold to the size amenable to the sample holder to be used (a shallow cylindrical mold with internal dimensions of either 10 mm or 25 mm in diameter and 5-10 nun deep is common in many SIMS instruments) 

Mixing an epoxy resin in this mold. Note The material used must be vacuum compatible. Specific resins that have been used include  

Applying the 20-8135 release agent to the mold before pouring the epoxy helps in puck removal 

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