EN ISO 11426:1998

Determination of gold in gold jewellery alloys - Cupellation method (fire assay) (ISO 11426:1997)

This standard specifies a cupellation method (fire assay) for the determination  of gold in gold jewellery alloys. The gold content of the alloys should preferably lie between 333 and 999 parts per thousand.

Bestimmung von Gold in Gold-Schmucklegierungen - Dokimatisches Verfahren (ISO 11426:1997)

Diese Internationale Norm legt ein dokimastisches Verfahren (Kupellationsverfahren) für die Bestimmung von Gold in Gold-Schmucklegierungen fest. Der Gold-Massenanteil der Legierungen liegt vorzugsweise zwischen 333 pro Tausend und 999 pro Tausend. Das Verfahren gilt insbesondere für Goldlegierungen, die Silber, Kupfer oder Zink enthalten. Für nickel- und/oder palladiumhaltiges Weißgold sowie für Legierungen, die mehr als 990 pro Tausend Gold enthalten, werden Verfahrensabänderungen angegeben.

Dosage de l'or dans les alliages d'or pour la bijouterie-joaillerie - Méthode de coupellation (essai au feu) (ISO 11426: 1997)

Določanje zlata v nakitu - Odtopitev primesi v tekočem svincu (ISO 11426:1997)

General Information

• Status: Withdrawn
• Publication Date: 15-Dec-1998
• Withdrawal Date: 29-Jun-1999
• ICS: 39.060 - Jewellery
• Technical Committee: CEN/TC 283 - Precious metalls - Applications in jewellery and associated products
• Drafting Committee: CEN/TC 283/WG 1 - Sampling and analysis
• Current Stage: 9960 - Withdrawal effective - Withdrawal
• Completion Date: 12-Oct-2016
• Ref Project: SIST EN ISO 11426:1999 - Determination of gold in gold jewellery alloys - Cupellation method (fire assay) (ISO 11426:1997)

Relations

• Replaces: EN 31426:1994 - Determination of gold in gold jewellery alloys - Cupellation method (fire assay) (ISO 11426:1993)
• Effective Date: 22-Dec-2008
• Replaced By: EN ISO 11426:2016 - Jewellery - Determination of gold in gold jewellery alloys - Cupellation method (fire assay) (ISO 11426:2014)
• Effective Date: 19-Oct-2016

Standards Content (Sample)

SLOVENSKI STANDARD
SIST EN ISO 11426:1999
01-november-1999
1DGRPHãþD
SIST EN 31426:1998
'RORþDQMH]ODWDYQDNLWX2GWRSLWHYSULPHVLYWHNRþHPVYLQFX,62
Determination of gold in gold jewellery alloys - Cupellation method (fire assay) (ISO
11426:1997)
Bestimmung von Gold in Gold-Schmucklegierungen - Dokimatisches Verfahren (ISO
11426:1997)
Dosage de l'or dans les alliages d'or pour la bijouterie-joaillerie - Méthode de
coupellation (essai au feu) (ISO 11426: 1997)
Ta slovenski standard je istoveten z: EN ISO 11426:1998
ICS:
39.060 Nakit Jewellery
SIST EN ISO 11426:1999 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST EN ISO 11426:1999

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SIST EN ISO 11426:1999

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SIST EN ISO 11426:1999

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SIST EN ISO 11426:1999

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SIST EN ISO 11426:1999

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SIST EN ISO 11426:1999
INTERNATIONAL ISO
STANDARD 11426
Second edition
1997-12-01
Determination of gold in gold jewellery
alloys — Cupellation method (fire assay)
Dosage de l'or dans les alliages d'or pour la bijouterie-joaillerie — Méthode
de coupellation (essai au feu)
A
Reference number
ISO 11426:1997(E)

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SIST EN ISO 11426:1999
ISO 11426:1997(E)
Foreword
ISO (the International Organization for Standardization) is a worldwide
federation of national standards bodies (ISO member bodies). The work of
preparing International Standards is normally carried out through ISO
technical committees. Each member body interested in a subject for which
a technical committee has been established has the right to be represented
on that committee. International organizations, governmental and non-
governmental, in liaison with ISO, also take part in the work. ISO
collaborates closely with the International Electrotechnical Commission
(IEC) on all matters of electrotechnical standardization.
Draft International Standards adopted by the technical committees are
circulated to the member bodies for voting. Publication as an International
Standard requires approval by at least 75 % of the member bodies casting
a vote.
International Standard ISO 11426 was prepared by Technical Committee
ISO/TC 174, Jewellery.
This second edition cancels and replaces the first edition ISO 11426:1993,
which has been technically revised.
©  ISO 1997
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced
or utilized in any form or by any means, electronic or mechanical, including photocopying and
microfilm, without permission in writing from the publisher.
International Organization for Standardization
Case postale 56 • CH-1211 Genève 20 • Switzerland
Internet [e-mail]
X.400 c=ch; a=400net; p=iso; o=isocs; s=central
Printed in Switzerland
ii

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SIST EN ISO 11426:1999
INTERNATIONAL STANDARD  © ISO ISO 11426:1997(E)
Determination of gold in gold jewellery alloys —
Cupellation method (fire assay)
1 Scope
This International Standard specifies a cupellation method (fire assay) for the
determination of gold in gold jewellery alloys. The gold content of the alloys should
preferably lie between 333 and 999 parts per thousand (�).
The procedure is applicable specifically to gold alloys incorporating silver, copper and
zinc. Some modifications are indicated where nickel and/or palladium are present in the
so-called white gold alloys, as well as for alloys containing 990 or more parts per
thousand (�) of gold.
This method is intended to be used as the reference method for the determination of
fineness in alloys covered by ISO 9202.
2 Normative reference
The following standard contains provisions which, through reference in this text,
constitute provisions of this International Standard. At the time of publication, the edition
indicated was valid. All standards are subject to revision, and parties to agreements
based on this International Standard are encouraged to investigate the possibility of
applying the most recent edition of the standard indicated below. Members of IEC and
ISO maintain registers of currently valid International Standards.
ISO 9202:1991, Jewellery — Fineness of precious metal alloys
3 Principle
The gold alloys are inquarted with silver, compounded with lead and cupelled in a
cupellation furnace until a precious metal button is obtained. After flattening and rolling,
the silver is extracted (parted) in nitric acid and the gold weighed. Possible systematic
errors in the procedure are eliminated by assaying standard proof samples in parallel.
NOTE — White gold alloys containing palladium and/or nickel as well as alloys with
...