My quest for the right "blue" gem

[the_mother_thing]

I feel like I have looked at every blue sapphire and spinel online, and even a few tanzanites, and I just don't know enough about how each stone will perform/behave to know which one would be right for my project. So, please, expert CSers, help me out.

I have a solid white gold mounting that I want to have engraved and add a few small old mine cut diamonds "scattered" about in the engraving for a RHR. I have talked with David Klass to take on this project; I just need to settle on and buy the center stone, which I want to be a nice medium (but not "electric" blue color. The stone would be semi-sunken into the mounting, so figuring out how that will impact the limited light entry into the stone, how much it will darken it up, how it will impact the visibility of facets, etc is what I wrestle with the most in deciding.

Here is the mounting which held a smidge over a 7mm OEC:



Here are some examples of inspiration rings to help understand my vision style, though the engraving won't be exactly the same:



I *think* I would like my "blue" to end up being medium to slightly dark in tone & saturation, but am not certain as I get these confused a lot. Somewhere in between the examples above, and I am flexible on this to some degree. I just don't want it to be super light blue nor "black out" once set. I want a nice contrast between the metal & stone color, would like to be able to see the faceting, but it doesn't need to be a disco ball; the accent diamonds will provide the sparkle.

I have seen some spinels I like, but am afraid they might black out in this setting since they seem to appear dark unless the light hits them just right, and with sapphires, I want to avoid color shifting to purple/violet (shifting from light/medium/dark blue is fine, just no purple).

I am not looking for a "top gem" here, and my stone budget is around $500, with a little wiggle room if needed. I am open to gem type, so long as it is durable enough for a ring (won't be a daily wearer), and delivers the right color. The mounting is currently set up to take a 7-7.2mm round, but in talking with David, I could go a little bigger or go oval by reworking the mounting. I don't want to go smaller in stone size though. I am okay with any stable/permanent treatment that doesn't compromise the structural integrity of the gem.

Is this an impossible quest? Or might you all have recommendations/gem suggestions that might work for my project? There is no hard deadline for this so I can wait for the right stone.

As always, thanks so much in advance for any gem suggestions, recommendations, guidance, etc you might provide.

 

[the_mother_thing]

Here is a candidate so far that is in budget and can work size wise for my project. I like this color as is, but not sure how it might darken. Any thoughts or feedback? It's from a seller I have bought from before and am comfortable with. Heat only. It's blown up a lot obviously and looks fuzzy but that is due to pic quality. I have seen a video of stone and I think it looks good, but am no sapphire expert.

ETA: it's from Madagascar & eye clean, if that helps. I have a question out to vendor about the dark line along the girdle.

 

[pregcurious]

If it returnable , that seems like decent buy

 

[the_mother_thing]

Thanks PregCurious. The vendor offers a full refund within a 10-day inspection period, and identified the dark line along the girdle as wax used to hold the stone during cutting, and he has since cleaned it off (I didn't see it in the video he provided). The stone measures 7.8 x 5.8 and weighs 1.58 ct. The price is approx $400. My preference is for a round so mods to the mounting wouldn't be required, but I haven't seen one yet in my price range & the color I am shooting for. This so far is the closest one I have come across.

Does it seem like a good buy? Does anyone know of a round in my price & size range?

 

[the_mother_thing]

Another candidate. This one is the preferred round shape, slightly larger at 7.6mm but $150 over budget. I can swing that, but only if it's thought to be a better stone/buy than the oval. It does look to have some violet/purplish undertones though, which I really don't want.