The Curta.org Bulletin Board

[murff]

What are Curta Fragments?

These types of items keep popping up:


[ Curta fragment Type 1 - source: curta.li ]


[ Curta fragment Type 2 - source: Auction Team Breker, Germany, 2026 ]

They are Curta fragments assembled from leftover parts. These Curta fragments were built at the former repair shop (Contina/Hilti)
in the 1970s and 1980s and sold to collectors. Since, at first glance, they bear similarities to the Curta demo models, they are
mistakenly described as such - and an inflated price is charged for them.

Description:
- These were assembled after production of the Curta had been discontinued (1971)
- Typically, the fragment consists of only a few parts from a complete Curta
- It is not functional; the round carriage is completely missing
- Typically, the fragment is mounted on an aluminum base
- There are Type 1 and Type 2 fragments
- Metal and plastic cranks are used
- A base plate is not always included


It's also important to note that Contina AG never manufactured a Curta Type 2 demo model. There are a number of retrofitted Curta
calculators in circulation that are falsely advertised as such - often at prices that are far too high.

It is not inherently wrong to purchase a Curta fragment or a Type 2 demo model. However, one should be aware that these items have
no historical significance or collector's value.

Estimated value/market price:
- Curta fragments (Type 1 or 2): no more than US$ 500.00
- Curta Type 2 demo models: approx. US$ 1,500.00 (the manufacturing costs are quite high)

- Genuine Curta Type 1 demo models from Contina AG: approx. US$ 5,000.00
- Demo model with the famous green box: depending on condition, US$ 8,000.00 to 12,000.00


_________________
:: m u r f f
:: curta.li

[murff]

Here is an example:


[ Curta Type II Calculator Demonstration Model, 1953 onwards ]


As of today (September 4, 2026), the auction house (Auction Team Breker) has not been willing to verify the facts in the
item description and make adjustments as necessary.


1) It is not a "model" - nor is it a "demonstration model"
2) It was not assembled by Contina AG
3) No functions can be demonstrated, as it is far from complete
4) It has no historical significance
5) It has no collector's value
6) The estimated value of 2,000 to 4,000 euros is completely exaggerated (plus a buyer's premium of about 30%).

How do you assess the item being offered?


links: liveauctioneers / the-saleroom (the auction ends on September 12)
_________________
:: m u r f f
:: curta.li

[Knetball]

Hello everyone,

I have to agree with murff. This type of machine has been known for years and is certainly not a demonstration model.

The lower base is the standard bottom part of the Type II machines, which has been machined on a lathe.

In this case, it is particularly easy to see, as the screw has been turned down as well.

I would even put my price estimate below murff’s.

The bottom plates without an engraved serial number, like the one in this case, can still be purchased.

Therefore, I can only advise against bidding on this lot.