<p>I have 9.5mm film from the 1930's which is still usable and projectable (although I've had the personal stuff of sentimental value transferred to video).</p>
<p>16mm and smaller has, SFAIK, always been "safety film" base, as compared with the flammable nitrate base of original 35mm., and I would expect that this would have been reasonable stable for many years. But, if your mother had treated the film with some unsuitable preserving fluid, this could perhaps have had a solvent effect on the base and made it brittle?</p>
