Sea Shells

I've decided to use iNaturalist to do an inventory of the sea shells I've collected over the years (marine gastropods only).
These shells have been collected between 5 to 15 years ago, in the Algarve region. Since I don't know the exact place or date in which every shell was caught, I'll be placing these observations as casual.

I took these pictures at night, on my desk, with my lamp and the flash of the camera as light sources - I can already see the pictures are too bright and lack detail, and I will re-do these observations if needed.
For the next couple of pictures I'll try to take them with natural light and without flash.
The purpose of this post is to, first of all, explain my goal, but also to ask for help. I'm not a expert in photography, and I don't have the best gear to take these photos but I'd appreciate some simple tips regarding the lighting part, should I used natural light? Direct sunlight? Is the white background better than the black (I do have a black mat on my desk that I could use)? If i need to take pictures after dark, what lights should I use?
And also, since all of these observations are going to be casual, I believe they will not get as much attention, so I wanted to ask anybody who is interested in these kinds of animals if they want to check them out after I post them.

I think that's all I had to say, thank you for reading, more updates should come some time soon.
Happy New Year!

UPDATE:
I have taken more pictures, this time using natural light and I think they came out better than the first ones, although the day was a bit cloudy.

All the observations are here:
https://www.inaturalist.org/observations?captive=true&d1=2021-01-01&d2=2021-01-10&iconic_taxa=Mollusca&place_id=any&subview=grid&user_id=tiagojrc&verifiable=any

Posted on 04 de janeiro de 2021, 12:53 AM by tiagojrc