Part of the decision-making process when it comes to preserving heritage is figuring out just what it is that is being preserved. Aging and material processes pull objects and sites out of their known forms; and as Tim Edensor sums up '[this erodes] their assigned functions and meanings'... 'blurring the boundaries between things.' (Edensor, 2005, p.318). A phrase used in environmental archaeology – to try and somewhat set these boundaries between forms – is mentioned by Caitlin Desilvey in her book 'Curated Decay: Heritage Beyond Saving': discovered objects can be classified as 'an artefact - a relic of human manipulation of the material world - or an 'ecofact' - a relic of other-than-human engagements with matter, climate, weather, and biology'. (Desilvey, 2017, p. 28). These terms are useful in discerning what might originate from the man made and natural world, however, they don’t necessarily help us when determining what’s what when it comes to objects that are fading away from their recognisable life. The terms 'artefact' and 'ecofact' seem to give us two ends of a sliding scale – and preservation intervenes somewhere along it, mostly before objects slip too far away from being artefacts. This is something that Desilvey describes when exploring and documenting a derelict homestead near Missoula, US. In an environment so full of objects – all at varying rates of decay – it is hard to say what is of significant enough value to save. Does an artefact possess more value than an ecofact? Or can 'a bundle of paper furred with mould' mean just as much as 'desiccated mouse carcasses'? (Desilvey, 2017, p.24).