Has anybody used these? Just noticed them listed on aqualab. http://aqualabtechnologies.com/concentrate-utensils/health-stone-glass.html?p=1 It lists them as concentrate utensils and says to absorb the consentrate on the stone then apply heat with a torch lighter. To me this seems like it would combust the oils or full melt you are trying to vape. However i think it would work good if you put a screen inside with some herb on it. Would work like the CD flame filter / glass vapor genie filter.