---
type: Object
title: The Standard Kilogram
description: The Institute's gold reference kilogram, the master standard against
  which Kelvarra's working weights are proved.
tags:
- kelvarra
- the-institute
- measurement
- instruments
resource: raw/aldervane-primer-extract.md
timestamp: '2026-07-16T15:03:08Z'
citadel_version: 0.3.0
---

# The Standard Kilogram

[The Institute](../organizations/the-institute.md)'s standard weights are made of gold, a choice the *[Aldervane Primer of Natural Measurement](the-aldervane-primer-of-natural-measurement.md)* says is "not extravagance": gold neither rusts, tarnishes, nor absorbs moisture from the air, so a kilogram of it stays the same kilogram over fifty years.[^s1] The Primer gives gold's atomic number as 82.[^s4][^llm1]

The standard kilogram itself is kept under glass and met by students in their second year; the Primer records the story of an assistant who sneezed near it in 1966 and was transferred to the tide gauges as a result.[^s2]

Lesser materials serve lesser posts: brass for the working weights, steel for the measures of length, quicksilver for the columns of the older barometers, and fused quartz for the optical bench — each detailed further in the [Instrument Works](../organizations/instrument-works.md)' own catalogue.[^s3]

## See also
- [The Institute](../organizations/the-institute.md)
- [The Aldervane Primer of Natural Measurement](the-aldervane-primer-of-natural-measurement.md)
- [Instrument Works](../organizations/instrument-works.md)

## Sources
[^s1]: [raw/aldervane-primer-extract.md](../../raw/aldervane-primer-extract.md), lines 40-43 — gold as the standard weight material and its stability (ingested 2026-07-16)
[^s2]: [raw/aldervane-primer-extract.md](../../raw/aldervane-primer-extract.md), lines 43-45 — the standard kilogram artifact and the 1966 anecdote (ingested 2026-07-16)
[^s3]: [raw/aldervane-primer-extract.md](../../raw/aldervane-primer-extract.md), lines 47-50 — lesser standards materials (ingested 2026-07-16)
[^s4]: [raw/aldervane-primer-extract.md](../../raw/aldervane-primer-extract.md), lines 41-42 — gold's atomic number as the Primer states it (ingested 2026-07-16)
[^llm1]: LLM - gold's real-world atomic number is 79 (82 is lead's); the in-world value is preserved as the Primer states it (added 2026-07-16)
