Mortar and Pestle for RNA Extraction - (Jan/31/2012 )

Our lab usually disrupts tissue with a Polytron, but since we planned to do extract RNA from pancreas, we have to use mortar and pestle set to grind the tissue in liquid nitrogen.

Our lab already has a set of Coorstek ceremic mortar and pestle. However, the lab manager appeared to have some concerns about its porosity (and by extension hard to decontaminate).

So, for those who routinely grind tissues with mortar and pestles for RNA:
<*>Is the porosity of ceremic mortar and pestle an actual concern for RNA extraction?
<*>If it is a concern, does that mean we have to buy the more expensive agate or AlO2 mortar and pestles?
<*>How do you decontaminate mortar and pestle between tissues? We may need to do several of them in a row.

Thanks for anyone in advance!

I used to use stanard mortar and pestles for DNA extraction - they were decontaminated in a 10% bleach (hypochlorite) solution. I don't see why the portosity would be a problem, as the tissue should not defrost while you are grinding, and if they are decontaminated straight away, there shouldn't be a problem.