As far as basketball parallels go, you'd be hard pressed to come up with a more popular set than the 1997-98 and 1998-99 Skybox Premium Star Rubies.
Premiering in the '96-97 edition of Skybox Premium, they started off as a non-serial numbered parallel, that if memory serves, averaged out at to one per box. The only thing that distinguished these original Star Rubies from the base cards was that the player's name and the Premium logo are in red instead of gold. A far cry from what they would later become. While still collectible, these don't seem to be overly desired at this point in time.
Skybox upped the ante with the '97-98 release by serial numbering them to /50, while also adding some short printed copies numbered to /25. If that wasn't enough, the surface of the card also now had a shimmery, almost refractoresque quality to it. Being numbered to /50 doesn't seem like a big deal today, but back then that was basically the modern equivalent of a 1/1. With no stated odds, most people seem to believe that they were seeded at around 1:1000-1500 packs. The odds could have even been more, but even by those estimates, they were a tough pull.
For the '98-99 edition, Skybox must have realized that they had a good thing going, as they didn't try to change things up to much. Besides a different base design, which was of course to be expected, the only real change, came in the different light-bending effects used for the Rubies. Still incredibly difficult to pull, this particular year of Rubies seems to be the most popular edition with collector's today.
Far less attractive than the previous two years, Skybox really dribbled the ball off their foot with the '99-00 release. The base card design was much less interesting, and the refractor-like quality that had made the set so popular, was now toned down considerably. And I guess in an attempt to up the collectability, the number was reduced to /45, which I don't believe ended up creating the desired effect. There is still a market for these, but most of them will go for far less than the two previous sets.
For all intensive purposes, Star Rubies as everyone knew them, ended after the '99-00 release. Trying to capitalize on past popularity, Fleer (owner of Skybox international) would later bring back the Star Rubies two more times, the first being for their 2001-02 Freer Premium set, these were Rubies in name only as seemingly they have nothing in common with the original run (plus their ugly as sin!). The second, and hopefully, final attempt by Fleer to cash in on the past came with the release of 2013-14 Fleer Retro. In this set they used Rubies as parallels to the '96-97, '97-98, and '98-99 Skybox Premium portions of the set. Fleer didn't (and still doesn't) have a licensing deal with the NBA, so while Rubies actually sort of look like they did, having the players pictured in their college uniforms really takes away from the overall aesthetic (at least in this humble blogger's opinion).
[Many thanks to Billy for pointing out that Fleer continued it's attempt to run the once beloved Star Rubies name in to the ground by creating an even more generic/uninteresting design for their 2002-03 Fleer Premium set. These failed to come up in any of my searches, after now seeing them, it's not difficult to understand why]
One does have to be wary of all the Taiwanese fakes that have flooded the market (eBay), I won't go in to how to spot the counterfeits here, as you can easily find that info via a google search, but I will say that they are pretty easy to spot (especially in person) once you know what to look for.
The 1998-99 edition of Skybox Premium was the last set I was working on before getting out of the card collecting game for next 10+ years. In late 1998 into early 1999, I was very enamored with the set, which led me to buy probably the equivalent of three boxes worth of packs. I pulled a lot of great stuff out of those packs, including a Ron Mercer Rubies, which I regrettably sold in the mid-2000's. The money from the sale was very helpful at the time, and I really didn't think I would ever be returning to card collecting, so I figured why not get what I could for it. Since returning to the hobby, that is one of the cards I really wish I still had, but maybe someday I will find another one at a price that works for me.
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