Thanks for posting your pics.
To help you going forward - using a black background causes your camera to average the exposure on the majority brightness...which is black in this case. Using a neutral gray or beige background will help the camera expose the marbles better and more details will show.
Keep collecting!
The 1950s classics - Watermelon, Spiderman, true Green Hornet(a lot of wannabe's and anemics out there). Oxblood on the first two seem appealing to many, but is incidental to the batch.