Is it Temuka if no stamps?

Hi everyone, I was left a considerable amount of Temuka Alpine Mist pottery by my late mum (or what I think it is anyway). Some have the Temuka printed stamp on the bottom but a lot or majority of it doesn't and some appear to be in stages of it being rubbed off or are partly missing. Is it normal for pieces to not have any marks or stamps? Can the wording rub off? Would appreciate any help. I've included some photos of some of the items as I was selling them but someone is questioning the authenticity. Also where else could I take them to confirm they're Temuka for their piece of mind? I'm based in Dunedin.

https://servimg.com/view/20473539/5

https://servimg.com/view/20473539/10

https://servimg.com/view/20473539/9

Hi Tessa, I saw your post on the Temuka Facebook page and can tell that all of the pieces that you posted match Alpine Mist.
Stamps don't fade away or fall off, but if they are not stamped properly when they are made it could look that way.
No other pottery was making this ware, so I am very confident when I say it was all made by Temuka Pottery.  Cheers

A link to Tessa's post on Facebook ...
https://www.facebook.com/photo?fbid=10161011087827018&set=pcb.5780377268709309

Oh great thank you! I thought it was weird that some have marks and some don't yet they look all the same pattern and make. I'll let them know and they can make a choice from there.