Grand Seiko 6146-8010 (Idemitsu commemorative)


The 6146-8010 is a notable watch for a number of reasons. It is often referred to as the “Arabesque” due to the graphic printing around the GS logo.

Introduced in the November 1969 edition of the Seiko Sales newsletter, and only on sale for a year, it was priced at a significant premium to the regular 6146-8000 model. Whilst the regular model had a retail price of 43,000 Yen, the -8010 was almost 50% more expensive at 60,000 Yen.

Interestingly, it was also simultaneously marketed in two versions for the same retail price – one with a faceted crystal, and one without. Possibly this was to test the market reaction to a faceted crystal – it was the first ever Grand Seiko to feature such a detail.

What is confirmed by the newsletter is that at least part of the increased retail price for this model was down to its use of a hardened stainless steel case and that the crystal – whether faceted or not – was sapphire. It has also been speculated that this model was regulated more accurately than the normal Grand Seikos, and was in fact the precursor to the Grand Seiko “Specials” that were introduced a year later.

The particular example offered for sale here is in pretty much mint condition. There are no signs of wear on the watch at all – not even any rubbing on the sides of the case between the lugs, which makes us suspect it could well be unworn.

But what is particularly interesting about this watch is revealed when you turn it over and look at the case back. This was not a watch that was ever on sale for the public. The case back itself is different to that on the retail models in that it has no markings on the outside to indicate the model number, material, or water resistance. There isn’t even a case serial number shown.

The reason is immediately apparent as one can see that there is a Japanese dedication engraved on the back of the watch. This dedication reveals that the watch was made to commemorate the 60th anniversary of the founding of the Idemitsu Corporation in the Showa 46 year. Showa 46 is the equivalent of 1971.

On removing the case back, one can find both the “missing” model number and case serial number on the inside of the case back. With the case serial number starting with 12, indicating production in February 1971, everything lines up.

To come across a regular retail example of this model in what is basically NOS condition would be remarkable enough. But to come across a never-sold-to-the-public commemorative edition in the same state is nothing short of miraculous.

On a timegrapher in the dial-up position, the watch is running at around -3 seconds per day.

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The 61GS series started production in 1967, and sales continued right through until the end of the vintage Grand Seiko era in 1975.

With seven different movements, there are as many calibers being utilised within this single series as in all earlier series combined. Not only that, numbering at 51 distinct releases, there are more individual 61GS watch designs than existed across those earlier series (the Grand Seiko First, 57GS, 44GS and 62GS).

As such, it isn’t really feasible to provide here a detailed overview of all 51 different models that were produced. However, an explanation as to the structure of the movement-caseback codes used in this series – along with a few examples – should suffice to give a high level perspective on the breadth and depth of the range. Information specific to the particular watch on sale will be included in that specific watch’s description that can be found under the price.

Movement codes

The first four digits of the eight digit movement-caseback code identify the characteristics of the movement utilised in the watch, although not – in the case of movements with multiple alphabetic suffixes (such as 6185A and 6185B) – necessarily the exact movement reference itself.

For the 61GS series watches, all produced by the Suwa Seikosha factory, the first two digits, “61”, as with all Grand Seiko references following the 5722-9990, represent the series itself.

The third digit, which for 61GS series will be a “4”, “5,” or an “8” is used to identify the quality of the movement from a chronometry perspective. The higher the number, the more accurate the movement.

“Regular’ 61GS models will be 614x movements, utilising the 6145A or 6146A calibres, and there are a total of 33 distinctly identifiable models. These movements were regulated to the Grand Seiko standard of -3/+5 seconds per day.

In the Christmas 1970 season, Grand Seiko introduced the “Special” 61GS models, which utilised either the 6155A or 6156A calibres. The movements in these watches were regulated to the “Special” Grand Seiko standard of -3/+3 seconds per day. In total, there were 9 distinct watches released utilising these calibres, which can be very easily identified because all of them have the word “Special” on the dial under the Grand Seiko logo. These watches were priced at a 10,000 Yen premium to their equivalent 614x powered models.

Finally, we have the 6185x and 6186x “VFA” movements that were first introduced to the market in 1970. “VFA” stands for “Very Fine Adjusted”, and these calibres were regulated to an incredible -2/+2 seconds per day, with the watches guaranteed to be accurate to within a minute a month for the first two years of ownership. Pricing for the VFA models started at 100,000 Yen.

The final digit in the movement code indicates the level of complication – a “5” indicates the calibre has a date complication, and a “6” indicates that it has a day-date complication. There are no examples of no-date watches in the 61GS series.

All 61GS series movements are 36,000bph automatic calibres.

Case codes

The final four digits of the eight digit movement-caseback code are used to identify the case of the watch. It is important however to note that there does not necessarily need to be consistency here where the same caseback code is used on multiple watches. This can lead to some confusion for the unwary, and it is why you can’t necessarily identify the exact model being referred to just from its eight digit movement-caseback code.

Just to provide a few examples to illustrate this –

No fewer than eight distinct models have the same 6145-8000 code. There are differences between these models both with respect to dial design, and case material. The full list of these models, along with the year of their introduction, and original prices, is as follows –

  • Stainless steel -8000 case; early Grand Seiko marked dial; supplied on a leather strap; 1968; 37,000 Yen
  • Stainless steel -8000 case; later Hi-beat marked dial; supplied on a leather strap; 1969; 37,000 Yen
  • Stainless steel -8000 case; later Hi-beat marked dial; supplied on a bracelet; 1970; 40,000 Yen
  • Cap gold -8000 case; early Grand Seiko marked dial; supplied on a leather strap; 1968; 45,000 Yen
  • Cap gold -8000 case; later Hi-beat marked dial; supplied on a leather strap; 1969; 45,000 Yen
  • 18K gold -8000 case; later Hi-beat marked dial; supplied on a leather strap; 1969; 190,000 Yen
  • Stainless steel -8000 case; Cross dial; supplied on a leather strap; 1969; 37,000 Yen
  • Stainless steel -8000 case; Cross dial; supplied on a bracelet; 1970; 40,000 Yen

Additionally, the same case code may be used across different movements, but the case design itself may not be the same across the different watches utilising it.

  • 6145-8030 has a sold 18K gold case
  • 6146-8030 has a stainless steel case
  • The designs of the cases for the 6145-8000, 6155-8000 and 6186-8000 models are all different

As will hopefully be evident from the watches available for purchase on this site, there is a tremendous variety of design in the 61GS series (with many models totally ignoring some, or even all, elements of the “Grammar of Design”), with watches available across a very wide range of price-points. Both entry-level and grail-level watches can be found in this series.



Additional information

Model number

Catalogue code

Dial code


Case Material

Year of manufacture

Dial colour



Movement type


Case diameter

Lug to lug

Internal lug width







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