085: The Pearlworks

ENTRY 085: The Pearlworks

The seas of Europa are, as researchers and explorers continue to discover, a distinct environment from the terrestrial waters that form the bulk of transhumanity’s ocean-lore. In the dark depths, where the pressure rises and the temperature drops, there are weird “rivers” of mineral-rich waters, heavier than the surrounding liquid, that can carve winding paths several kilometers long before the differentials in temperature and mineral content even out, and the “river” becomes indistinguishable from any of the other currents. These edge zones between warmer and cooler waters are prime habitats for some of Europa’s deep-sea lifeforms, particularly lithoderms that depend on the mineral-rich waters for sustenance.

The most spectacular of these under-ocean rivers is the Pearlworks, which emerges from the cone of Mt. Nacramater, a massive cryovolcano encrusted with Europan coral. The icy cryomagma sluggishly slips of the side of the underwater mountain, forming the first in a series of half-frozen waterfalls as gravity and density force the semiliquid downwards to the surface of a relatively flat plateau. Eventually pressure and temperature shifts force the emission into a liquid state, and it feeds into thirteen-kilometer winding canyon, gradually expanding in width and becoming more shallow as the mineral-rich waters diffuse into the open ocean.

The Pearlworks are home to one of the most unusual species on Europa, the Europan pearl. These creatures begin their life as seed-like multicellular organisms consisting of three thin tissue layers—an outer layer that filters the surrounding waters, a middle vasculature and transport layer, and an inner layer packed with symbiotic lithoderms. The minerals that the pearl absorbs but cannot digest are passed to the lithoderms, who process it and excrete it inside the growing seed-pearl as a spherical or near-spherical mineral nodule, causing the pearl to stretch and expand its surface area, allowing it to better capture additional minerals. The process is slow and the Europan pearls are not entirely without predators, but some of the oldest pearls have reached truly prodigious size—over one meter in diameter for the Grand Pearl of Europa.

Explorers in this underwater world have captured images of entire stretches of the Pearlworks filled with tiny, almost spherical nacreous seed-pearls, the light playing off their low-index outer membrane and high-index inner-membrane to produce strange optical effects in the dark. Some of the larger animal-analogue fish have been known to scoop up small or mid-sized Europan pearls; the exact reason is unknown but most xeno-   oceanographers believe it is either for the mineral content or to facilitate grinding and digestion.

Seeds

• Europan pearls are living creatures, sensitive to environmental stress and damage to their outer membranes. A smuggler in the PC’s colony has arrived with a high-pressure container with a dozen inch-diameter Europan pearls, and gotten themselves arrested. Now several factions are tearing the habitat apart looking for the container. The PCs may find it difficult to stay neutral as various groups form looking for the treasure, but unbeknownst to them all it is for naught. Cramped and neglected, the Europan pearls in the container have died and their outer layers peeled off, leaving behind rough spheres of unremarkable minerals.
• Miners in the Europan depths have been harvesting pearls from one of the branches of the Pearlworks whose nodules contain high concentrations of platinum-group metals. An environmental engineer has tried to convince them to use the pearls to find the load rather than to harvest the Europan wildlife directly, but without success. So she wishes to prove them wrong directly, by staking a rival claim at the load itself. If the PCs are willing to back her up and protect her, she’ll give each of them a share in the claim.