The Marteau Early 18th-Century Currency Converter

Our Conversion Rates : Table

A Note on Our Default Conversion Rates Step 1: The Paritius rates of 1709 Step 2: Our Additions and Changes — The Russian Rouble — The Ottoman Gurush — The Portuguese Réis — Geneva's Florin — The Pound Scots — Japan's Momme Silver — India's Rupee — Persia's Toman Step 3: Use Your Own Rates

Pond Vlaams

1/1

fl. Netherlands

4/25

1/1

£ sterling

9/16

9/100

1/1

Reichsthaler

5/2

2/5

40/9

1/1

lb. Fr./ fl. pol./ mk. Lub.

15/2

6/5

40/3

3/1

1/1

Reichs-Gulden

15/4

3/5

20/3

3/2

1/2

1/1

Lire, Venice

75/4

3/1

100/3

15/2

5/2

5/1

1/1

Russian Rubles

5/4

1/5

20/9

1/2

1/6

1/3

1/15

1/1

d.s:mt Sweden

5/1

4/5

80/9

2/1

2/3

4/3

4/15

4/1

1/1

Spanish Reals

1425/68

57/17

1900/51

285/34

95/34

95/17

19/17

68/95

285/68

1/1

Portuguese Réis

2005/1

321/1

3565/1

802/1

267/1

535/1

107/1

1604/1

400/1

96/1

1/1

Ottoman Gurush

125/32

5/8

125/18

25/16

25/48

25/24

1/8

25/8

25/32

17/285

1/513

1/1

fl. Geneva

105/4

21/5

140/3

21/2

7/2

7/1

7/5

21/1

21/4

119/95

10/764

168/25

1/1

Pound Scots

117/16

117/100

13/1

117/40

39/40

39/20

43/30

117/20

117/80

663/1900

1/274

234/125

39/140

1/1

Jap. momme 80% silver [* 3]

62.5/*

10/*

111/*

25/*

8.33/*

16.7/*

3.33/*

50/*

12.5/*

2.98/*

0.03/*

16/*

2.38/*

8.55/*

1/1

Russian Roubles 1700

75/28

3/7

100/21

15/14

18/35

5/7

1/7

15/7

15/28

17/133

1/749

24/35

36/245

100/273

3/23.5

1/1

Indian Rupees

45/8

9/10

10/1

9/4

3/4

3/2

3/10

9/2

9/8

5/19

1/356

36/25

3/14

10/13

3/10.5

21/10

1/1

Persian Tomans [* 416 2/3]

62.5/*

10/*

111.11/*

25/*

8.33/*

16.7/*

3.33/*

50/*

12.5/*

2.98/*

0.03/*

16/*

2.38/*

8.55/*

3/*

23.5/*

10.5/*

1/1

lb. Vl.

fl. Nl.

£ sterl.

rthl.

lb. Fr.

fl. SIR

lb. Ven.

Rus.

d.s:mt Sw.

Sp. Real

Port.

Otto.

Genev.

Scot

Jap.

Rus. 1700

Rupee

Pers.

first number horizontal, second vertical, SIR: Sacrum Imperium Romanum, Germany and Austria

A Note on Our Default Conversion Rates

Step 1: The Paritius rates of 1709

Most of our conversion tools are based on the conversion rates Georg Heinrich Paritius used in his Cambio Mercatori published in three editions in 1707, 1709 and 1717. The 1709 edition offered a preface with a short history of the book claiming that the author had one of his pupils copy a book published by "Georg Heinreich Fykklaß" consisting of "38 tables, printed in 12mo in Amsterdam by Johann Minelle two years ago." That could be 1707 if seen from 1709 or 1705 if seen from the first edition published in 1707. We have not been able to identify the source. The rates Paritius used as the basis of his arithmetical exercises were, however, common European rates. Isaac Newton refers to some of them from 1702 to 1725 when asked for advice on larger transactions. We have not followed Paritius with his data on the Russian rouble

The table above gives the Paritius rates in the first (gray) block.

Step 2: Our Additions and Changes

The Russian Rouble

The rate Paritius gave for Russia's roubles was either wrong or outdated. Information Vasilii Vasil'evich Uzdenikov provides in his book Monety Rossii 1700-1917 (Moskva: Izdatel'stvo Datastrom, 1992) demands a rate in which 7 Dutch gulden will match 3 Russian roubles. Dutch Leeuwendaalders, silver Riders and silver gulden were used to give the revised exchange rate for the first years of the 18th century.

The Ottoman Gurush

Şevket Pamuk's rate for is based on historical sources and a comparison with Dutch Leeuwendaalders, the latter having been the most frequent Dutch coin of trade in the area.

The Portuguese Réis

Nuno Valério used for his exchange rate of the Portuguese Réis the known rate against the British pound.

Geneva's Florin

The exchange rate for Geneva's guilders is based on Martin Körner's, Norbert Furrer's, and Niklaus Bartlome's Währungen und Sortenkurse in der Schweiz (Lausanne, 2001).

The Pound Scots

The rate for the pound Scots followed Isaac Newton's remark of the discrepancy between the regular rate of 13/1 against the pound sterling and the more precise rate which would have respected the metal values of the coins involved – here again we opted for the accepted (rather than the "accurate") rate.

Japan's Momme Silver

The momme was (and still is) a unit of weight matching 3.75 g. Our rates give equivalents for silver of a fineness of 80% and are taken from a comparison with the Dutch Leeuwendaalder and the regular Dutch silver gulden. They have been set to get a common denominator of 3 in order to allow changes of the fineness of Japan's silver - one momme of 80% fineness has a silver content of 3 g. Silver of 50% as it was minted after 1695 contained 1.88 g silver per momme, the alloy of 20% fineness minted in 1710 contained 0.75 g silver the momme. Silver as minted for the trade with Korea in 1710 preserved the 80% fineness and the 3 g silver minted before 1695. Change the denominator according to the silver amount you guess you are offered. See the special page on Japanese money for details.

India's Rupee

We have included conversion tools for Indian, Dutch and English money, the rate of 1 pound equalling 10 Rupees was contemporary and matches a comparison of coins. See the special page on India's money for details.

Persia's Toman

Persia's currency was an unpleasant candidate due to the Toman, Persia's unit of accounting used to for larger sums of money, the toman being a unit of (unstable) gold equivalents, all supposed to match 50 silver Abbassi of a regular coin weight of 9.33 g. We have brought the conversion rates onto a common denominator of 416.667 to give a plausible silver equivalent in grams and to facilitate modifications. 416 2/3 g of fine silver should be the equivalent of one Toman if you want to make 50 Abbasi match the Toman, and if you want to keep in line with rates at which 3 Abbassis were changed into one regular Thalers. Willem Floor mentioned larger early 18th century sums with the equation of 425 Dutch guilders matching 10 Tomans - the difference is within the tolerance at which Dutch coins made a gulden (of 9.6 or 10.2 g) fine silver. Conversion rates remained beyond this effective silver-fixing a matter of agreement. See the special page on Persia's money for more insight.

Step 3: Use Your Own Rates

Our conversion tools calculate with the default rates you see at the bottom of each page – you can change these entries to calculate with rates of your own choice — Possible alternatives could be:

The Newton Mint Assay of 1702, we have prepared a table for that purpose.

A computation with silver contents and data we selected.