Thexar-VI: Khal-Vex-El — Sha-El 07: Khal-Thel Sha-Thar — Materials Science

"A terrestrial engineer asks: what is this made of? We ask: what does it want to become? Material is not dead clay in the hands of a creator. Material is a junior partner in the work." — Guild of Engineers, "Foundations of Matter," +3 140 Y.E.

Ruun-ak rass: → rhu [Thexar-VI, Sha-El 01, "Thel-ak Khal-vex"], → rhu [Thexar-VI, Sha-El 03, "Xha-Ven Khal-sha"], → rhu [Thexar-VI, Sha-El 09, "Vex-Thel Khal-sha"], → rhu [Thexar-I, Ruun 33, "Khar-mor rass Thel-ak-mor Khal-vex"] Mor-ven: Materials science stands between geology and biology, belonging fully to neither. The wealth of Théxar (iron enrichment 2.8, thorium 2.5, platinum 2.2) gave an abundant base — and symbiogenesis determined what to do with it: not to cast and forge, but to grow. A modern material is not manufactured but bred — like a plant cultivar.

7.1 The Six Classes of Matter

Classification adopted by the Guild of Engineers in +2 480 — senary: 6 classes, 36 families, 216 standard grades.

The fundamental difference from terrestrial classification: Xha'Ruun divide by relation to life — from entirely dead metals (3) to entirely living colonies (5). Class 6 is the summit because it unites the dead and the living.

7.2 Class 1: Osseous Materials (Thar-Vex)

The main construction material — grown by builder organisms on the principle of mineralization of a biological matrix.

Self-healing: a thin living-cell layer along grain boundaries heals cracks up to 0.24 m in 14–40 days. The material must be fed a solution of silicon salts and traces of H₂S through channels (~4% of mass). When feeding stops it "falls asleep": strong but no longer self-repairing.

Limitations: fails below −60 °C; degrades above 40 Gy/year; unsuitable for melt contact; growth cannot be accelerated (doubling the rate reduces strength fourfold).

7.3 Class 2: Crystalline Materials (Ven-Khal)

Silicon-carbide crystals grown from a melt: hardness 6/6, failure temperature 2 730 °C, conductivity 490 W/(m·K), transparency 0.2–14 μm, service life >10⁹ years.

Three applications beyond memory: optical windows (portholes, lenses), heat removal (plasma circuits), resonators (a crystal with given lattice defects has a defined natural frequency — the basis of all resonance technology). Largest farms on the Raal plateau (48% of platinum, used as a growth catalyst); a fist-sized crystal grows 12 years.

7.4 Class 3: Metallic Materials (Tor-Khar)

The only class inherited from pre-industrial eras; copper production dates to −9 200.

The paradox of metals: their share in structures fell from 74% (+1 000) to 19% (+4 028). Metal is "dishonest" — it does not age visibly, breaks suddenly, gives no signs of fatigue. Xha'Ruun engineering values materials that warn about their condition. Metal remains indispensable in reactor circuits, tools, conductors, and ritual art.

7.5 Class 4: Carbon Materials (Xa-Thar)

Almost never used pure — they are the reinforcing phase in class-6 composites. Exception: the orbital elevator cable, where carbon-silicon bundles work inside a self-healing Thar-Vex-24 sheath.

7.6 Class 5: Living Materials (Xa-Vex)

Materials that remain fully functional organisms. The boundary between "material" and "creature" is the subject of constant ethical disputes.

The bio-membrane — one-way gas permeability, powered by the film's own metabolism — makes non-hermetic orbital stations possible. Ethical restriction: organisms with nervous tissue, and anything capable of learning, are prohibited as materials — what remembers cannot be a thing.

7.7 Class 6: Composites (Rass-Thar)

Not assembled but grown jointly: the reinforcing phase grows through the matrix in a single process.

Rass-Thar-F — an inter-species material, developed with the Kel'vash after their entry into the Council (+1 200). Kel'vash secrete it with their own metabolism; payment and voluntariness are regulated by the Treaty of the Three Species.

7.8 Testing and Standards

The concept of honesty of material — the ability to signal approaching failure.

The honesty test has no terrestrial analogue: a sample loaded to 90% is observed for pre-failure color, smell, or frequency change. A material that fails without warning is not admitted to structures with living beings — regardless of strength. The return test (≥96% of mass to production or biosphere) was introduced in +1 640 as a consequence of the memory of the ecological collapse of the First Empire (−2 150).

7.9 History of Materials

The turning point — +1 812: the first grown load-bearing beam instead of a cast one; its anniversary is the guild's professional holiday.

7.10 The Limits of the Possible

• Strength limit of matter — the carbon nanotube (130 GPa) is the theoretical maximum.
• Temperature limit of the living — no living material above 1 400 °C.
• Growth-rate limit — growth cannot be accelerated; a large structure requires years.
• No negative-mass metamaterials — a consequence of the ban on anti-gravity.
• Vacuum — living materials need traces of atmosphere; in open space only the dead or dormant phase works.

Ruun Ven

1. Six classes — from dead metals to fully living colonies; classification by "relation to life."
2. The main construction material is the self-healing Thar-Vex; a crack up to 0.24 m heals in 14–40 days.
3. Metals were displaced not by superiority but by the "honesty of material" standard.
4. Rass-Thar-F is the first material produced jointly by two sentient species — secreted by living Kel'vash.
5. The return standard (≥96%) was introduced in +1 640 in response to the memory of ecological collapse.