I have zircons that have been mounted in a resin block. They have been polished to approximately half way through the zircons (as is convention) and they have been ablated to attain the U-Pb or Pb-Pb ages. I am unfamiliar with the intricacies of the (U+Th)/He method. Can these zircons still be analysed for (U+Th)/He? Or would the ablation affect the results? Furthermore, would the zircons need to be extracted from the resin blocks? If so, what would be the best method of extraction?