Refined gold ingot ZlA-4, GOST 28058-2015

The ZlA-4 ingot is an industrial form of refined gold with a mass fraction of Au not less than 99.90% and total impurities not more than 0.10%. The letter «A» indicates refined metal, and the number 4 denotes the chemical composition grade.

Specifications

• Metal: refined gold
• Grade: ZlA-4
• Gold: not less than 99.90%
• Total impurities: not more than 0.10%
• Standard: GOST 28058-2015 with current amendments

Item number: 5203442. Actual parameters are confirmed by the batch quality certificate.

Purpose and applications

• preparation of gold-containing alloys after calculating the impurity balance;
• remelting into technological blanks and semi-finished products per specification;
• materials science work where the Au 99.90% standard is sufficient;

Quality control

GOST specifies the shape of a truncated pyramid: larger base 254±5 by 88±5 mm, smaller base 229±5 by 59±5 mm, height 35±8 mm. Standard mass ranges from 11,000 to 13,300 g; other shapes, dimensions, or mass are possible upon agreement. Each ingot is checked for mass, surface, and marking; composition is attributed to the batch from a single melt.

What to confirm before ordering

Specify the mass of the particular ingot, melt number, actual gold content, impurity control results, and the set of accompanying documents. For further alloying, define acceptable elements, losses, and requirements for the final blank. Do not confuse this item with the standard for investment gold bars: format, purpose, mass, and handling procedures differ.

Storage and handling

Store the ingot in protective packaging, preventing scratches, contamination, mechanical damage, moisture, and vapors of sulfur compounds. Marking, number, and mass must remain legible and linked to the certificate. Receipt, transfer, and processing are accompanied by precious metal accounting; samples, chips, and melt residues are collected and documented separately.