Pyrusite appears to primarily take on a the shape of a large, teardrop-shaped gemstone glowing with a vivid orange-red light, almost as if lit from within by it's namesake element.

Pyrusite has been observed to be, extremely hot to the touch with a single touch being enough to burn ones hand. Pyrusite also appears to be... extremely resistant to heat, as even the temperatures from the Genesis Forge seem incapable of even beginning to melt it down.

While, Pyrusite does not naturally exist on the Material Plane, it has been theorized that it could potentially be found in abundance in the Ever Burning Planes within Prometheus's Domain

While Pyrusite was indeed recognized among the legendary Lost 24 Primordials, its existence in the Material Plane predates recorded history far more significantly than previously understood. Unlike its peers, which vanished into obscurity, traces of Pyrusite extend deep into historical timelines, with its earliest documented presence dating back to the early 4th Era, shortly after the catastrophic fall of Ygdrassil.   At that critical juncture, AzKaThas, a formidable elder god of the Arcruxes, endeavored to craft a legendary artifact known as the Pyrus Saber. This blade was forged from a material known as firesteel, an experimental precursor and prototype form of true Pyrusite. The forging process, inadvertently more potent than anticipated, released a cataclysmic surge of primordial energy, igniting the planet Dragnier and transforming it into the radiant Star World it became famously known as during the 4th Era; Dologancy.   The resulting Pyrus Saber became an heirloom of the illustrious Thassadar family, continually reshaped and reforged through generations. Its form evolved alongside its wielders until it was entrusted by Azure to Elesis, coinciding with Elesis' own transformation into a Pyrusaiyan. Despite its significance, the blade’s true composition remained undiscovered, even when later passed to Eliza in the twilight moments of the 5th era, preceding the climactic Twilight of Imagination.   It wasn't until 70 years following the cataclysmic events of the Twilight of Imagination that the enigmatic substance known as Pyrusite resurfaced into historical prominence. Aurora Ai, conducting pioneering research aboard the Aberration ARK, uncovered critical insights that allowed her to replicate authentic Pyrusite. Leveraging this knowledge, she harnessed the recreated Pyrusite as the central power source for the devastating Wrath of Prometheus, subsequently deployed on the planet below.   Following Aurora’s return from the ARKs, prompted by Kazumachi’s insightful suggestion, Aurora sought Eliza's permission to examine her blade. This investigation culminated in a groundbreaking revelation: the Thassadar family heirloom, now wielded by Eliza, was constructed entirely of Pyrusite. This discovery unequivocally confirmed Pyrusite as one of the exceedingly rare Primordial substances to have naturally existed within the Material Plane. Nevertheless, the precise circumstances or methods by which AzKaThas originally acquired genuine Pyrusite remain shrouded in mystery.   Three months after the groundbreaking findings from the Borealis Expedition, Aurora Ai gained special permission to utilize Ramon's forge facilities. She carefully used a minute fragment of her newfound Pyrusite sample to create the very first Igniting Blade. This innovative weapon later became a celebrated addition to the Nexus Depot, heralding a distinctive line of Starter Weapons accessible to adventurers embarking on their journey within the Nexus.

While originally believed to be Aurora who first discovered this Lost Primordial in the Modern Era, later revelations uncovered by Aurora revealed that this is not the case, with AzKaThas somehow having access to the element far earlier than was understood, using it to forge the Pyrus Saber early into the 4th era.