Volcanic Lava Rock

Volcanic lava rock is a potentially identifying trace in the investigation of Borgny Stem-Myhre’s murder: unusual gray-black stones found at her crime scene resurface as similar material in the cellar of police headquarters. The comparison offers a concrete lead, but not a conclusion. The rock’s geological origin would need to be established by analysis, and the wider investigation shows why that distinction matters: clues pointing toward Tony Leike can be part of a deliberately misleading trail.

The stones at Borgny Stem-Myhre’s crime scene

The forensic report on Borgny Stem-Myhre’s death describes two small gray-black stones on the concrete floor of the cellar where her body was found. They did not match the gravel at the scene. The report offered a possible account of how such stones might have arrived there: stones can lodge in the deep tread of boots and fall out when the wearer walks across a hard surface. That mechanism suited the condition of the floor, but it identified only a plausible route, not the person who had carried the stones or the place from which they came.

The absence of other ordinary traces made the stones especially noticeable. The concrete had been cleaned the day before, in preparation for installing heating cables and flooring. Investigators therefore had no shoe or boot impressions to examine, alongside an absence of fingerprints and DNA. In that context, two loose fragments that differed from the site’s gravel acquired evidentiary weight: they were among the few material traces that might have travelled in with someone from elsewhere.

The report also recorded a separate detail relevant to the broader pattern of the killing. Iron and coltan traces were found on the inner surfaces of two of Borgny’s molars. Those findings do not establish that the stones came from the same place, or that the rock caused the mineral traces. Their importance is that geology and distinctive materials recur in an investigation where the origin of objects may connect crimes to places—and may also be used to direct suspicion toward them.

A resemblance in the police cellar

Later, during work in a tunnel area beneath police headquarters, a criminal technician picked up a black-and-gray fragment and asked whether it looked like the small stones found at Borgny’s crime scene. Harry Hole examined it and identified it as volcanic rock. The exchange revives the earlier report’s unexplained stones, turning them from an isolated curiosity into a possible link between locations.

That link remains provisional. The technician points out a visual resemblance; Harry’s identification establishes the material as lava, not its particular volcano of origin. The evidence does not show that the cellar fragment and Borgny’s stones have already been matched through laboratory testing. Instead, the discovery prompts a specific comparative question: whether the new material comes from the same volcano as a previously submitted sample. The distinction between recognizing a material and proving its source is central to what the rock can—and cannot—show.

The cellar discovery also gives the clue an unusual setting. A trace first noted in a murdered woman’s cellar appears again within the police building, where investigators are revisiting the case. The recurrence makes the rock conspicuous, but the fact of recurrence alone cannot explain how it reached either site. Its evidentiary value depends on tracing that movement rather than treating resemblance as proof.

Geological comparison and its limits

When Harry takes a small stone to a woman at a house and asks whether it came from the same volcano as one previously sent for examination, she refuses to assess it by sight. Lava is not compositionally interchangeable: each volcano has a characteristic composition, and that composition can vary from one eruption to another. The stone must be analyzed, she explains, and its iron content can provide useful information. This answer replaces an easy visual identification with a testable geological question.

The conversation establishes a practical limit on the clue. Calling the fragment volcanic rock narrows the material category, but does not identify a volcano, eruption, or route of travel. Even a match in broad appearance would need to be checked against composition. The emphasis on iron is particularly suggestive alongside the iron traces reported on Borgny’s teeth, but the evidence does not state that the two findings have the same source or demonstrate a direct connection between them.

The woman’s own knowledge of volcanoes supplies a concrete example of why visual appearance can mislead. She describes a recent visit to Ol Doinyo Lengai in Tanzania, where an eruption produced sodium-carbonatite lava. The lava emerged black and turned white after exposure to air, within a few hours. Her example shows that a rock’s appearance can change with its composition and conditions; it does not identify the sample Harry brought as material from that volcano. The conversation therefore sharpens the need for analysis rather than resolving the sample’s provenance.

The clue within a misleading trail

The lava trace sits within a case in which geographic evidence has already encouraged a mistaken focus. Beate Lonn challenges the team to consider the apparent evidence against Tony Leike, including a call from his landline to Elias Skog’s phone and a murder weapon obtained in the Congo, near an economic project associated with Leike. Harry acknowledges that the Kavalier had directed the investigation toward Leike from the beginning. The Kavalier had paid Juliana Verni to travel to the Congo because a trail leading there would inevitably draw attention to Leike.

That disclosure does not establish that the volcanic rock was planted by the Kavalier, nor does the material alone identify the person who carried it. It does change how investigators must treat a geographic clue: a trace that appears to point toward a suspect may reflect the real history of an object, or an effort to manufacture that appearance. The distinction is especially important when the presumed destination or source is the Congo and the resulting association makes Leike look culpable.

The stones’ narrative and forensic function is thus deliberately double-edged. Their difference from the gravel at Borgny’s scene gives investigators a reason to preserve and compare them; the later resemblance in the police cellar supplies a new line of inquiry. Yet neither observation is a completed identification, and the geological account insists on the intervening work of analysis. Volcanic lava rock matters not as a self-explanatory token of guilt, but as a material clue whose meaning depends on provenance—and whose apparent meaning must be tested against the possibility of manipulation.