Hi Lucie,
Your pearls, although you don't give a size, look like freshwater pearls, which are being sold in Bangladesh a lot now according to a discussion on another thread on this forum. The pink would probably be natural color button freshwater, and the dark ones dyed freshwater. If you look a little on ebay you will get an idea of what they are worth, as you will see many similar items.
Pattye
so many pearls, so little time