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Topaline (symbol To) is a chemical element, atomic number 117 on the periodic table.

Characteristics and history

Topaline, in its most stable form, has an atomic mass of 318, and was discovered by the Humans for the first time on Ganymede in the year 2021. This metal is part of the trans-uranic series of heavy elements. (ST reference: Star Fleet Medical Reference Manual)

Topaline, found in rare ore, can be processed to be used to maintain life support systems, and has been known to disrupt sensors.

In the 22nd and 23rd centuries, topaline was a highly-prized mineral by the Klingon Empire and the acquisition of the mineral led to several tense engagements with the United Federation of Planets, including Capella IV. (TOS episode & Star Trek 3 novelization: Friday's Child; TOS novel: First Strike)

The planet taD, conquered by the Empire in the mid-22nd century, was a key source of topaline. After the 2220s, however, the Klingons had discovered dozens of worlds rich in topaline, lessening taD's importance. (TNG novel: Diplomatic Implausibility)

In 2267, the United Federation of Planets main source of topaline on Altimara was running out, and Capella IV was viewed as the best replacement source. (TOS - Star Trek 3 novelization: Friday's Child)

That year, as regent for Leonard James Akaar, Eleen Akaar signed a treaty allowing the Federation to mine topaline on Capella IV in exchange for annually providing the Capellans one metric ton each of castrodinium and trititanium. (ST reference: Federation: The First 150 Years)

In 2355, the planets and moons of the Maxia Zeta star system were discovered to be richly endowed with many minerals including topaline. (TNG - TLE novel: The Buried Age)

Trinni/ek, a planet discovered in 2380 by the USS Io, had large supplies of topaline and other minerals. (ST novel: Articles of the Federation)

In the wake of the Borg Invasion of 2381, there was an increased demand for topaline for refugee habitats. (ST novel: A Singular Destiny)

In 2409, Starfleet considered the independent Aelas system a major source of topaline in the Beta Quadrant. (STO - Romulan Mystery mission: "Saturday's Child")

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In real-life science, element 117 has been identified as Tennessine, one of the more stable synthetic super heavy elements. Subspace science mentioned in Star Trek may account for the contradiction of this being a resource on other worlds.


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