What type of cat do I have

We adopted Sienna last year from the shelter when she was 8 weeks old. She has very unique markings and coloring. People always ask us what type of cat she is, and what her coloring is called. We have no idea what type of cat she is or what she is mixed with. what do you think she is mixed with  and what is her coloring called? no matter what she is mixed with, we love her so much. I attached several photos of her now and when she was a kitten. thank you in advanced

 Th

here is one more pic of her

She is a tortoiseshell, possibly also a tabby (does she has stripes on her body?   I dont the the typical M on the forehead, but I think I do see stripes on her sides).  If so, she is a torbie.

The colors are blue and cremé, ie diluted black and red.  She has also some white on her.

I dont get clear on her breed look alikes.  Technically she is a domestic, of course, and is probably for real, alike most of all cats.  But she MAY have some recent mix from some purebred ancestor.

Nice  to see her apparently being a good pal with the ferret.   I dont think cats and ferrets are natural enemies, but they are certainly competitors in roughly the same food nisches if living in the wild..

Thank you StefanZ for the reply.

She does have some stripes on her front legs and some on her side. I think you are right about her being a torbie, I looked them up and she looks similar to them.

and yes, she and the ferret are best friends. they play together and sleep together. the ferret absolutely loves Sienna. 

It's not a real color term, as far as I know, but I would call her a silver torbie and white.  She is technically a dilute torbie and white, it sounds like--but usually dilute torbies are bluish and cream.  It looks like her blue has silvered out.  From time to time I will come across blue tabbies that are silver in hue and I call them silver tabbies, so I would call her a silver torbie/white.

To explain a little further.  A tortoiseshell is black and red.  Red is always tabbied, but when the black is tabbied (in the form of brown tabby patches), it's called a tortoiseshell tabby or "torbie" for short.  Diluted black and red are blue and buff, so a dilute tortoiseshell ("tortie") has stripes in the buff parts but solid blue patches.  If the blue patches are tabbied as well, that makes it a dilute torbie.  Because her white patches don't take up most of her body and/or separate her color patches (I have heard both requirements and either/or for a calico) she is dilute torbie and white, versus dilute calico.

And as earlier, she seems to be silver instead of blue.  She is a strikingly colored cat and I'm not surprised you get a lot of questions.  Domestic cats are a muddle of genetics so really most color combinations are possible, but that is not one I've seen much before.

That photo of her as a kitten with the flowers is adorable. Her nose has really darkened, hasn't it?  She is priceless.