Are these pearls Tahitian or dyed?

[Cats&pearls]

Hi everyone!
I received a strand of pearls from my aunt like 10 years ago. I don’t know anything about their origin, but I think she had had them restrung or the clasp redone. At the time I was told they were black pearls. I want to get some advice from Pearl lovers about the type of pearl that they are. I’m not sure if they are dyed freshwater, or Tahitian. In photos with flash, they appear to be black, but there is a lot of variation and definition in the color. Any input will be greatly appreciated!

 

[jshepherd]

They are dyed Chinese freshwater pearls.

 

[Cats&pearls]

They are dyed Chinese freshwater pearls.

Is it because of the variation in shape?

 

[Pearl Dreams]

No it's more than that. The eggy shapes, sizes and the colors and overall appearance all point to their being freshwaters.
There is no question about it.