79 Au Gold
Au salts & complexes

Chloroauric acid (hydrate)

CAS 16961-25-4

Chloroauric acid is the universal soluble gold source — the precursor behind gold nanoparticle synthesis, electroplating baths, supported gold catalysts and gold recovery chemistry.

Specification

Typical specification

Molecular formulaHAuCl₄ · xH₂O
Molecular weight339.79 (anhydrous basis)
Purity (metals basis)≥ 99.9%
Gold content≥ 48.5% (certified per lot)
AppearanceYellow-orange crystals
Water solubilityFreely soluble
HS code (export)2843300000

Lot-specific COA issued with every shipment. SDS and ICP elemental impurity data available on request.

Applications

Where HAuCl₄·xH₂O is used

Gold nanoparticle synthesis

The starting material for citrate, seed-growth and Brust-type gold nanoparticle syntheses used across diagnostics (lateral-flow assays), plasmonics and catalysis research.

Plating and catalyst manufacture

Feeds gold electroplating and electroless baths for electronics, and the deposition–precipitation route to supported Au catalysts for CO oxidation and selective hydrogenation.

Handling & logistics

Storage and shipping

Storage. Store tightly sealed, protected from light; strongly hygroscopic and corrosive.

Shipping. Corrosive (Class 8) classification applies; shipped in UN-approved packaging. Gold compounds are subject to additional export formalities — confirmed per order.

Packaging. 1 g · 5 g · 25 g · 100 g · Solution grades by contained Au weight

Also searched as

Synonyms

  • Hydrogen tetrachloroaurate
  • Gold chloride acid
  • HAuCl4
  • Tetrachloroauric acid
FAQ

Frequently asked questions

How is pricing structured?

Quotes reference the day's gold price on assayed contained metal plus a stated conversion charge, lockable at order confirmation.

Are gold compounds harder to export?

Gold-bearing goods carry additional trade formalities in some lanes; we confirm the compliant routing and documentation per destination before accepting the order, so your shipment clears without surprises.

Do you take back spent material?

Yes — residues and off-spec lots are assayed on receipt and the recovered metal credited against your next order.