Testing – METTLER TOLEDO Case Study: A Special Scale to Weigh a Giant Gold Coin

METTLER TOLEDO (Czech Republic) – The Czech National Bank can prove that its commemorative gold coin weighs 130 kg (287 pounds). In fact, they know it weighs 130.24 kg, thanks to the accuracy of METTLER TOLEDO instruments. This coin is one of the largest engraved coins in the world.

To celebrate the 100th anniversary of the Czech-Slovak currency, the Czech National Bank issued a special gold coin with a nominal value of 100 million CZK (4.4 million USD at publication).

Jaroslav Moravec, PhD, Chief Expert at the Department of Monetary Circulation and Currency Protection at the Czech National Bank, thought of the idea to manufacture and issue the giant coin. The Swiss company, Metalor, the Austrian Mint in Vienna, and the Czech Mint all worked together to make the coin.

METTLER TOLEDO service technicians weighed the final coin with a METTLER TOLEDO High Precision Bench Scale (Model PBK987-CC150) and a Weighing Terminal (Model ICS685). Weighing such a large coin was not at all a simple task.

Absolutely Precise Teamwork:

The team from METTLER TOLEDO worked under time constraints, under challenging environmental conditions, and even under the watchful eye of film makers to deliver precise measurements.

Tadeáš Hlaváček, a METTLER TOLEDO Service Technician, spent twenty-four hours over a two-day period — preparing, installing, and calibrating the equipment. He needed to control for winter conditions at higher altitudes, since the Czech Mint is located in the mountains. He also made a special frame to weigh the large coin and another frame for the scale to eliminate external forces during the weighing process.

Video Coverage:

Tadeáš mentions an unusual challenge, "As the coin is so important for the history of the Czech nation and the Czech National Bank, professionals filmed us during the weighing process. It was quite difficult to do correct work while also following the film director´s wishes."

For more information see the Making of the Coin Video, subtitled in English.

Like Weighing a Newborn Baby:

Lukáš Běhal, Regional Manager, Guarantor in the Weight Field at the Czech Metrological Institute, was in charge of managing the measurement process, processing the results, and issuing the calibration certificate. "Weighing a gold coin of this size was an exceptional experience. My job is to measure and weigh, but never before did I have the opportunity to weigh something that beautiful or valuable. We were weighing pure gold valued at CZK 100 million, so even the slightest damage had to be avoided. It felt very much like weighing a precious newborn baby."

Coin Display:

Once the coin was finished, it was put on display at Prague Castle, a UNESCO World Heritage site, to commemorate the 100th anniversary of the Czech-Slovak currency. The coin exhibit was popular with the public. It is now on display at the Czech National Bank in Prague, as part of the public treasury of the Czech Republic.

Did Yo Know?

The gold coin is legal tender, though it will likely never be used as a method of payment. The nominal value is fixed at 100 million CZK. The nominal value is lower than the actual value of the gold to prevent speculation if the value of gold were to fall.

Picture 2 Caption:

This 130 kg gold coin is one of the largest engraved coins in the world.

Picture 3 Caption:

Tadeáš Hlaváček, a METTLER TOLEDO Service Technician, prepared, installed, and calibrated the equipment.