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I'm looking for a story I read about 40 years ago in which there is memory retaining glass... At first people place sheets of the glass in lovely places, so that it can be fitted into a window frame and give the house's owners a lovely view, with e.g. birds flying over, weather, etc.
Later in the story the uses turn a little more sinister and particles of the glass are used to spy on people - one thing I remember is a woman brushing her husband's shoulders for glass to see if he's been unfaithful! - but I think the implication (if it wasn't stated) was that once all privacy is gone, how we live changes radically. (Implications for social media and tracking technology... I'd love to read this now! Some ideas just haunt you...)
Does anyone know this story and where I can find it?