Hitherto unknown lifeforms
If one were able to bring an inanimate, inorganic, material to life, what lifeforms would it be capable of generating. This question is germane to understanding how to recognise the emergence of life in hitherto inanimate objects. To project definitions of life taken from organic lifeforms would be a poor choice.
A better approach would be to consider how life could manifest itself within the physical constraints to which the inanimate material is subject. Taking as an example a metal, such as copper, it is clear that whatever lifeforms are engendered will have limited - if any - mobility, given the rigidity of the metal, even in its annealed state. So if one imagines that a sign of life might be that the metal changes appearance - say colour or hue - in response to the environment, then it is not inconceivable that copper that is living would show colours that change depending on, say, ambient light.
When considering hitherto unknown lifeforms we need to free our minds from the confining grip of the organic definition of life, and distill this to its purest and most general meaning.