Dating and storage advice please of my Austin family Photograph

[CAW53]

This picture was among a box of pictures I 'inherited'. It appears to be on black glass substrate and the image is susceptible to scratching (I currently store it in a plastic box surrounded by cotton wool).
Firstly, can someone give me an idea of what date this is likely to have been taken, and
Secondly what is the best way to store/preserve the photograph.
Thank you

[McGroger]

Sorry, I can't help with your requests, Caw, but moving it up the board might get it seen by the experts.
Peter

[AJ100]

An early tintype/ambrotype/daguerreotype image dating from around 1860/70 (Jim will put me right on this). The image was reversed as if looking in a mirror. Children's clothes are difficult to date as they stayed constant for many years. Is that a mourning brooch the lady is wearing?

AJ

[Gadget]

I think it might be 1880s but not enough of the mother's dress showing to be definite.

Gadget

[jim1]

1860's Ambrotype.
Strange the top of her head is cut off.
Looks like mother wanted the best image of the baby but the relatively primitive lenses couldn't manage both.
Keep storing it the way it is now. Make sure the back is well protected as any damage to this surface will result in loss of image.