Jade, rose quartz, and obsidian have closed porosity and are safe to use. They will not cause TSS (Toxic Shock Syndrome). The amount of bacteria (staphylococcus aureus and group A streptococcus are those associated with TSS) that would temporarily get on the egg is negligible if they’re exposed. We don’t have exact percentages of porosity since this is extremely difficult to measure at such low levels. A study shows a specimen of quartz, for example, to have 0.39% porosity. A typical rock would have 15-20% porosity.
Also, TSS is a risk when a woman wears very absorbent material (such as a tampon) during menstruation when pH levels rise, and even then, the risk is extremely small. Yoni eggs aren't used when we have our period, and they're the opposite of absorbent!
It doesn't hurt to be extra careful, so we suggest you sterilize your eggs by cleaning them properly! Again, yoni eggs are safe to use internally, and reports claiming otherwise are alarmist and inaccurate.