and thanks for the [amazingly] prompt reply. I read the abstract of the article.
Previously you have said that [all] Gallstones sink/do not float. So can I take it that you are of the opinion that completely uncalcified stones sink, even though they are mainly composed of cholesterol, which itself is lighter than water? In which case, you presumably believe that the remaining mass of non-calcified cholesterol Gallstones is significantly heavier than water, for the composite mass to be incapable of floating. Can you says what is this 'other', heavy part of non-calcified gallstones?