For sale we have an excellent and timeless ladies tank watch from the early 1930s, produced by Alpina Gruen Guild collaboration. It is small yet mighty with its considered design and high-quality manufacture. It has a 14k yellow gold case of a rectangular form, with engraved case sides and floral engraved boarder to the rear of the case. To the right is a neat Sapphire Cabochon crown. The champagne dial has a railroad track for minutes, with stylised Arabic numerals. The thermally blued hour and minute hand tell the time. Inside the case is signed by Gruen with 14k gold singing. The movement is a beautiful Gruen 833 calibre, manufactured by Aegler, which is the same as the Rolex 250.
 
Alpina Gruen Guild history:
In 1929, German brand Alpina joined forces with the American watch company, Gruen. This created the Alpina Gruen Guild (Gilde). This cooperative allowed the brands to pool resources and maximise their productivity throughout Europe and the US. Alpina could take advantage of Gruens strong distribution network in the US. Gruen were aiming to penetrate the European market following the uncertainties of the Wall Street Crash. 
 
The watches produced in the period were of excellent quality, selling well, with the cooperation coming to an end in 1939 under the strain of world war.
 
Hermann Aegler, who supplied movements for Rolex, also sat on the board of Alpina and was a vice-president of the Alpina-Gruen Gilde. This allowed both Alpina and Gruen to take advantage of the high-quality movements used by Rolex in the era.  
 
A more famous sibling of the collaboration during the period was the Alpina Gruen Tecno, a doctors dial watch which had the same design and movement as the Rolex Prince. 
 
This example:
The case is of neat proportions measuring 13.5mm wide x 26.5mm in length. An incredibly timeless design with a shallow depth of 6.3mm. It is rectangular and is formed of 14k yellow gold. It has excellent engraving to the case sides and back which are well executed. The sapphire cabochon crown is a neat and classy touch. A watch that really resembles the classic design of Cartier, but for a fraction of the price. 
 
The champagne tone dial has Alpina Gruen signing to the centre, with a rectangular railroad treack following the line of the case. The stylised Arabic numerals are very pleasing. The thermally blued spade and plume style hands shine brightly in the light and tie in nicely with the tone of the sapphire cabochon. 
 
Inside the case is signed Gruen 14k, Cincinnati, 833/8. This matches with the movement calibre, which is a Gruen cal 833, which is the same as a Rolex 250, with both being supplied by Aegler. It is an excellent quality movement which has been recently serviced. 
 
This is an excellent and standout art deco ladies watch, with the quality of a Rolex and the design of a Cartier, whilst maintaining its own neat touches and DNA. For the price you will not find many better made watches, with this having the benefit of an interesting collaboration and story in history too. 
 
Full condition report below. Please see the images as these compliment and aid the description provided below.
 
Dial: 
The champagne tone dial is original and is in decent condition. It has a simple rectangular railroad track with stylised Arabic numerals which is clear. The Alpina Gruen signing is clear too. There is marking and patination consistent with ageing.
 
Hands: 
The hands are original of Spade and Plume style. They are in good condition with no bending or corrosion. The thermally blued tone is bright. 
 
Glass: 
The acrylic crystal is a replacement which is in very good condition with no marking.
 
Crown: 
The gold tone crown is original, with sapphire cabochon inset. It has some nicks and signs of ageing to the cabochon.  
 
Case:
The case is formed of 14k yellow gold and is in very good condition with light surface scratching. It has a polished finish with a good shine to the front. The sides have a floral engraved border in good original condition. 
 
Caseback:
The case back holds the movement and is formed of 14k gold. It is in good condition with a polished finish and light surface scratching associated with ageing. It has an engraved floral border which is in good original condition. 
 
Strap: 
The watch comes on black genuine leather strap in good condition for fixed lugs.
 
Movement: 
The movement is a Gruen calibre 833. It has a jewel count of 15 and a frequency of 18,000 BPH.
 
The movement has been serviced. It’s keeping time to +60 seconds a day, with an amplitude of 255 degrees and a beat error of 0.8m/s.
 
Case dimensions: 
Case width: 13.5mm
Case width with crown: 16mm 
Case length: 26.5mm 
Case length lug to lug: 28mm
Case Depth: 6.3mm
Lug width: 12mm