They look like they might be colour change Diaspore.
What tools do you have to help you Id them?
The stone is most likely double refractive ( Colour change)
Do you have a carat scale? so you can find the specific gravity? you can find instructions on IGS
Do you have a black light and a strong magnet? Here is a simple test you can try. Float the stones in water, if you have a piece of foam that will work well. With a strong magnet see if they are either attracted or repelled by the magnet.
If you can calculate the SG then you will help you narrow it down.
Alexandrite- SG is 3.7 3.73 - Very weakly magnetic reaction or none if it is synthetic- Should glow Red Pink under UV
Diaspore is about SG is 3.3 will react to magnetism and turn yellow / green under UV light
Colour change Garnet SG is about 3.65 , Very strong react to magnetism ( should be picked up by the magnet) but typically inert to UV light
These test are not conclusive on their own but together they can be a very good indication. They are relatively simple to do at home with very little equipment. SG may vary as will the magnetic and UV reactions but it is a good guide line.
Good Luck, have fun