Proof of Trust and Reliability

Good Delivery Referee

TANAKA is working to create a global standard for precious metals.

TANAKA is the only accredited Good Delivery Referee in Japan that assesses accredited precious metal refiners to ensure the quality of globally-marketed precious metals. TANAKA also produces analytical reference samples for solid emission spectrometry, which serve as a global standard for the precious metal industry.

TANAKA appointed Good Delivery Referee, demonstrating the world-class standard of its technologies

In December 2003, TANAKA was accredited as Good Delivery Referee for gold and silver by the London Bullion Market Association (LBMA), the most prestigious trade organization of the global gold and silver market.

In order to offer high-quality precious metal materials and assembling parts in the electrical and electronic industries, TANAKA has been developing high-standard metal processing technologies that produce high-purity metals (gold: 999.9) for many years. In addition, TANAKA is approved with its highly skilled ability to produce accurate alloy reference samples to assess accredited refiners. With its assay precision, TANAKA can also inspect and evaluate samples manufactured by refiners.

There are only five Good Delivery Referees in the world, and their roles are to (1) assess the gold and silver melting technologies and analytical skills of all accredited gold and silver refiners and (2) accredit new refiners.

TANAKA's appointment as a Good Delivery Referee is signifying the global recognition that its melting technologies and analytical skills receive.

TANAKA's appointment as a Good Deliver Referee proves that:

Production of analytical gold reference samples for solid emission spectrometry

For a project established by the world's leading precious metal-related companies and led by the LBMA, TANAKA was commissioned to produce the industry's first globally recognized reference sample for gold analysis. TANAKA was able to produce the sample successfully thanks to its proprietary technologies for the production of homogeneous alloys and the precision alloying of various elements. Since July 2009, the reference samples have been selling throughout the world by the LBMA.

TANAKA assumes a main role in the market as an LPPM-approved Good Delivery Referee.

In April 2009, TANAKA was appointed as a Good Delivery Referee for the London Platinum & Palladium Market (LPPM). Since then, TANAKA has been striving to polish our analytical and assessing skills. There are only five LPPM Good Delivery Referees in the world at present, and TANAKA is the only one in Japan.

The LPPM, which was established in May 1987 after experiencing precursor's long history, is the only globally recognized organization in the world that accredits refiners in order to ensure that platinum and palladium transactions are conducted fairly.

In June 2009, the LPPM posted its Good Delivery Rules on its website and launched a re-accreditation system (referred to as "Proactive Monitoring (PAM)", to follow the same system as LBMA which had been introduced for gold and silver in 2004) for platinum and palladium. As a Good Delivery Referee, TANAKA's mission is growing in scale.

Platinum and palladium are used as important materials in an even wider range of industrial fields than gold and silver. These fields include the automotive, electrical, and electronic industries, as well as the asset trading markets. Needless to say, given its high-level analytical skills and its advanced technologies and abundant experience in the field of industrial precious metal processing, TANAKA is expected to play an increasingly prominent role in the LPPM.

With its involvement in the LPPM and the core specialties built up over the years, TANAKA remains committed to making a significant contribution to the world.

We undertake contract manufacturing of standardization samples for optical emission spectrometry. Please contact us for further details.

TANAKA has also been accredited Good Delivery Bars for Commodity Exchange Inc. (COMEX) and the New York Mercantile Exchange (NYMEX).

Our Analytical Techniques Support Customer Confidence in TANAKA

We meet customer expectations through the various instruments, techniques, and high-level skills we employ.

As a company dealing with precious metals, we believe that assay values form the foundation of the confidence that our customers and society as a whole have in us. Given this, we continue to strive to improve analytical accuracy and develop new technologies.

Classification of Analysis based on Purpose and Analytical Methods

Classification based on Purpose

Fire assay

This is a special method used to analyze the purity of gold and is conducted by skilled assayers for accurate evaluation.
(The same method as used at LBMA)

Gravimetric Analysis

In this method, liquefaction is used to catalyze a chemical reaction that separates gold or platinum from samples, enabling the weight of the particular precious metal to be directly measured. This long-established method requires great care but offers a high degree of accuracy. It is for this reason that this technique is handed down from one generation to the next.

Instrumental analysis

An instrument is used to take simultaneous measurement for an analytical sample and a reference substance with a known concentration in order to obtain assay values. From a variety of analytical instruments for "inductively coupled plasma-optical emission spectrometry" (ICP-OES), "X-ray fluorescence spectrometry", "atomic absorption spectrometry", "glowdischarge mass spectrometry" etc, we select the most suitable one depending on the purpose so that we can conduct quick and accurate analyses.

Towards International Standards

Accredited to ISO/IEC17025

At the Planning and Development Office, TKG Laboratory Center, we are honored to be Japan's first organization accredited to ISO/IEC17025 for gold analysis technology.
Accreditation scope
Simultaneous analysis technique of metals (36 elements) in gold (Au) bullion using an ICP optical emission spectrometry based on the following standards:
JIS H 6310: Methods for determination of gold in gold jewelry alloys,Section 8
JIS K 0116: General rules for atomic emission spectrometry (except Section 6)

We plan for further ISO/IEC17025 accreditation for Pt and Pd bullions.

ICP optical emission spectrometer

Our ISO/IEC 17025 certificate

Note: ISO/IEC 17025 is the international standard that defines the general requirements for competence in testing or calibration.