Well, just from digging on the rocks, but as you can see I can't buy more Ruby from the table, at least with the specific SIM having the issue, as this doesn't happen with any other.
The table as such do not have any option to purchase any gems. Did you try to purchase a ruby from a computer or were you unable to do that.
When clicking on the table and selecting Cut Gem with All selected are you unable to scroll down to the ruby and select that? If not can you post a screenshot of what you see there. The screenshots of inventory that only showed that there were no ruby there are pointless as you had already told us that and we all know what a ruby looks like.
Well, the screenshot of the Ruby was to show you it appears as if it were on my inventory/the table.
On the "Order Tab" on the computer it only shows "Medicine. Books. Upgrade parts. Seed", no gems there. And since it's showing as if it were on the inventory I'm unable to do the purchase from the table directly, like when you don't have the material so you can just purchase it, I can't do that with the Ruby.
For example, I do have a quartz and I can use it with no issues, but when clicking the Ruby and hitting "Confirm" nothing happens, at all.
So when you select the Ruby and get to this dialog
You can't click the checkmark to proceed.
Try doing a factory reset as described in this post: http://answers.ea.com/t5/The-Sims-4/FAQ-Troubleshooting-Steps-amp-Known-Issues/m-p/3621199
