> I'm not sure what you mean by "saturated" Saturated means no more crystals will dissolve at that temperature Super-saturation is a temporary condition - when the solution cools down the excess will recrystallise and drop out > and I'm not sure what you mean by "board" "Board" is the unetched stock > But I"m sure that the 1/16" FR4 boards I'm using are denser than > the ferric chloride I'm using :-) Well, I've yet to find a board that sinks, phenolic or GRP "sinks" means not on the top anymore, drowning, gurgle gurgle "top", as in........... -- http://www.piclist.com hint: The list server can filter out subtopics (like ads or off topics) for you. See http://www.piclist.com/#topics