At the very centre of the Variegated Patina, shrouded by obnoxious amounts of gas and dust, lies one of several anomalous "throwback stars". While undoubtedly known due to its brightness beforehand, its presence was first pointed out to the Ecumene in early telescopic surveys as a sixth-magnitude star with a highly anomalous "population III" spectrum. Only hydrogen and helium were present in the star's envelope- but only after centuries of surveys and arguments, well into the interstellar period, were its true anomalies revealed. It became obvious that beyond likely being an artificial replica, the star was even beyond the excesses of a population III star- rather, it was an even more theoretical entity. Someone had gathered nearly a hundredth of the mass of the three hundred light-year nebula and used it to make an homage to the chaotic early years of the universe- a quasi-star, or gold postfusor. A gold postfusor features a vastly inflated envelope reminiscent of an grossly oversized yellow hypergiant- but at instead of rampant fusion at its core avoiding collapse, a black hole rages at the center of a metastable supernova. The only reason it wasn't brighter than every other star in the sky was the nebula- the knots and whorls of gas brought its brightness down by twelve orders of magnitude.
Of course, it wouldn't be possible to examine the Variegated Patina, let alone its bright heart, for millenia- but clues were picked up as the Ecumene expanded. Million-year old astronomical annals on a dozen worlds reported the nova of its formation, and as ships crept ever-closer to the nebula more details could be revealed. Finally, an expedition made the fourteen-year (at the time) journey over starting in 4341. While observing the star from its nearest companion 3 light-years away (behind the inner dust, it was still -10th magnitude), they made the decision to pierce the veil of gas and dust and view the star from a closer vantage point. As they attempted to head to a half light-year, where the star would shine as if they were in a perfectly normal yellow star's habitable zone, a problem became apparent: their drives relied on a gravity well flattening to operate, and the entire center of the nebula (out to twenty light-years) was already deep within the star's gravity well. The only way to get nearer would be to find another star orbiting deeper- and the highest magnitude they could expect for another star within that morass would be below the visible range. After a full year of searching, they headed home- dismayed and excited in equal measure.
The second expedition retained 80% of the first's crew, and was nearly twice the size. After another twelve years of travel (sped up due to better drives and better mapping), they brought their deepwell drives up and headed past the final layers of the veil. Even at the vast distance half a light year, the star's own vastness meant its disk could be discerned with the proper filters. Countless rocks, planets, and brown dwarfs orbited- though a black hole of the same mass would have hosted more, due to its considerably greater age. Likewise, stabilization systems became obvious- of a different pedigree to those that would be found later in the Chloric Vault, but with the same purpose of keeping the Variegated Patina stable and not dispersing under the influence of such a huge single mass.
It would take two millenia more for the Variegated Patina to be reachable by fleets not specifically intended for such long expeditions. It'd take another millenium and a half for the Variegated Patina to be colonized to the extent that the settlement there could become a proper sector. This was partly due to centuries of contention between arrivals from the Ecumene, explorers from equally distant powers, and natives of the few systems old enough to develop intelligent life in and around the Variegated Patina- polities from all three occasionally claiming to have created the quasi-star. Today, Sector 592- uncreatively named Patina Sector- is perhaps even more cosmopolitan than its distant sibling in the Chloric Sector. More technological and cultural trade takes place there than on any of the Ecumene's other borders. The bounty of close-together stars in the Variegated Patina exceeds even the largest nearby clusters... but everyone wants a good look at that gold postfusor.