OP, I appreciate that you are taking the comments seriously, and working towards being in compliance with eBay's policies.
Taking note of your new name change (australianethicaldiamond), are you changing your stock to laboratory-grown diamonds? I will say that taking an ethical approach to precious stones is a powerful thing to do. There's no doubt about the heartbreak and misery which diamond-mining has caused and continues to cause, and after all, if we value a stone for its chemical properties, brilliance, resilience and beauty, there is no reason to favour a natural diamond over a cultured diamond.
(I don't favour the term synthetic diamond very strongly, as it gives a misleading impression. A diamond produced in a laboratory with the techniques available today is not only as beautiful and strong as a natural diamond, but even more so. Laboratory-grown diamond or cultured diamond are two terms that in my view are far more apt. For marketing purposes, I think cultured diamond couldn't be bettered.)
However, if your stock will remain mid-range (AAA) machine-cut cubic zirconia, your username may lead buyers to assume that you deal in laboratory-grown diamonds, since one of the main marketing strategies for these diamonds is that they are ethically produced rather than unethically mined.
If you are still going to be selling the CZ jewellery, be prepared for disappointed buyers who will be expecting a thousand-dollar ring for under a hundred dollars. It sounds preposterous, I know. But lord, oh lord, the number of times I have heard people speaking of their extreme cunning in grabbing an incredible bargain, only to be outraged and disappointed beyond all imagining when they find that their "incredible bargain" was not that, and that they had paid for a replica/imitation/non-brand copy/simulated stone rather than precious stone/etc., etc., etc.
It's only going to get worse. The descriptions on eBay are always being skipped by many buyers - especially ones who use their smart devices to buy. eBay is already presenting items in searches in the most ridiculous and confusing way, requiring buyers to find the right link to click onto in order to see what they're actually seeking!
So ... do everything you can, if you're still going to focus on selling CZ jewellery, to inform the buyer about exactly what they are buying. Don't rely on the price; I've seen even otherwise sane and logical people turn into frothing look-what-i-got-for-a-fraction-of-the-pricers on eBay and on other online shopping sites. We've seen it time and time again on these boards, too - far too many people who come here to post of their disappointing purchase to whom the oft-repeated advice "If it's too good to be true..." is given, only to fall on deaf ears.
I did take a very quick look at your listings, to ensure I knew how you were presenting the items. I can see you're using the term simulant (except in the tennis bracelet) in the title. Make sure you specifically include simulated as required by eBay policy. This will enable buyers who are specifically looking for diamonds to exclude the word simulated in their search.
I'd also not use the word "excellent" for the cut in item specifics. These are machine-cut, not hand-cut. They're not excellent (in my view, and not as an objective measure). You can think about how to describe the quality of the cut, but I think the best you could do is say "very good - see grading and clarity specifics for further details". With the clarity being VVS1, again, err on the side of understatement.
I do want to make the point again that a ring whose value is under $100 is not really suitable (in my opinion) in our culture to be marketed as an engagement ring. I take note that some people will certainly be looking to minimise their costs as a young married couple, and won't be going all out on an engagement ring. Still others will consider a simulated stone to be just as good as a precious stone (and certainly a lot cheaper). Of course there's no doubt that the intention and motive in giving an engagement ring is more important than the value of the ring. Withal, I do think that an engagement ring is something special and that making an effort to get something that does justice to the occasion means that a $35 CZ ring is not going to cut it. (Even the care instructions in your listing acknowledges tacitly that these stones are considerably more vulnerable to damage than a diamond, or a high quality hand-cut CZ, for instance.) There's a difference between spending insanely too much (even going into debt for some ridiculous mammoth of an engagement ring) and insanely too little. That's why I think a better customer base for you to market to will be women looking for a pretty dress ring, some costume jewellery of decent quality.
