In 1786 during the great political and administrative reform that involved the whole structure of Austrian Lombardy the ancient guilds of art were abolished, but silversmithing was privileged, obtaining special attention.
In Mantua special police measures were adopted by the political intendant Gherardo d’Arco, who on September 25, 1787 asked Giovanni Bellavite (appointed representative of silversmiths) to compile the new regulations which actually confirmed most of the old regulations of the Art.
Also the ancient marks were maintained at least until 1792 when the new representative of silversmiths, Giacomo Antonio Bosio (Mantua 1722 - Mantua 1798), was authorized to continue the practice of marking silverware with the old symbols.

Ancient silver marks used in Mantua before the new regulation introduced in 1786 by Austrian Government

On February 2, 1797 Mantua surrendered to the French Army and, with the Treaty of Campoformio, became part of the Cisalpine Republic. In 1805 Napoleon was crowned King of the new Kingdom of Italy and Eugenio Napoleon Beauharnais settled as Viceroy in the Royal Palace in Milan. On December 25, 1810 a new system of rules for the manufacture and trade of gold and silver artefacts was approved by the Viceroy. The new regulations, inspired by French laws, consisted of 110 articles which imposed a system based on three marks and new symbols were approved to identify the quality of the metal alloy and the Assay office location.

The new mark used to warrant the 800/1000 silver alloy was a heptagon containing the World (or the globe) surrounded by the seven stars (or trioni, from ancient Latin: triones) of the Great Bear constellation. The Mantua Assay Office was identified by the symbol of a “Swimming Swan”, but with a new decree dated 14 February 1812, only the offices of Milan, Venice, Bologna, Ancona, Verona and Brescia were activated … Mantua and its swan were obliged to wait… Mantua silversmiths were forced to present their silverware to the Verona Assay Office, and, despite numerous petitions, the request to activate the Mantua Assay Office was rejected by Authorities. Indeed, the difficulties grew in 1814, when the second Austrian domination and redefinition of boundaries obliged Mantua silversmiths to go even further distances to obtain the assaying of their products.

This situation had an influence on the number of silversmiths’ active in Mantua and many of them preferred to become silver and gold retailers trading artefacts manufactured and marked by other workshops.
Scarce silver products with Mantua marks are locally preserved and most early 19th century silver has Milan, Brescia or Venice marks.
An example is this spoon with the globe (mondo and trioni: silver fineness 800/1000), plough (Milan assay office) and Gio Battista Sala workshop mark (GBS with two crossed swords and crown).

silver 800/1000 spoon with Milan assay office mark and Gio Battista Sala workshop mark

Also Brescia’s silver articles were imported in large quantities into Mantua, and this assay office used the symbol of a "spear’s top". An example is on the spoon manufactured in Domenico Roveglia workshop bearing the mark with "DR and tree" (note 1)). In this case the "globe" is replaced by the "anvil", used as "small items" fineness warranty.

Silver 800/1000 spoon bearing Brescia assay office mark and Domenico Roveglia workshop mark. In this case the "globe" is replaced by the "anvil", used as "small items" fineness warranty.

The petitions of Mantua silversmiths obtained a result only in 1831, when the local assay office was opened and the "Swimming Swan" symbol was activated (note 2).
Following these considerations, it’s reasonable to suppose that most of the artefacts bearing only the workshop mark were manufactured in the period 1810-1830.
An example is this spoon made by Mantua’s silversmith Luigi Martelletti (1775 - 1852) marked only with "lamb and cross" (emblem of St. John the Baptist) and letter "M" (see for comparison the mark on the tag presented to the assay office in 1811) (note 3).

Silver spoon bearing only Luigi Martelletti workshop mark (on the left the mark on the tag presented to the assay office in 1811).

Even the spoon bearing the "Swimming Swan" is characterized by shape and decoration typical of the first half of the 18th century. This "violin" handle, markedly concave and simulating a superimposed second stem, is inspired to Venetian production, largely followed by Mantua silversmiths. The "double" stem ends with a stylized trefoil contour (note 4). The stem is marked with the "Swimming Swan" and the "globe", while the workshop mark is rubbed out. The stem is also engraved with owner’s initials "IAF".

NOTE

(1) R. Massa, Orafi e argentieri bresciani nei secoli XVIII e XIX, Brescia 1988, p 113

(2) The " Swimming Swan" mark (introduced with the Royal Decree of 25 December 1810) and the three marks system were repealed with the law issued by the new Kingdom of Italy (unified) on May 2, 1872 (see V.Donaver-R. Dabbene, Argenti italiani dell'800, vol.I Punzoni di Garanzia degli Stati Italiani , Milan 1987, P. 14; and S. Barraja, I marchi degli argentieri e orafi di Palermo dal XVII secolo ad oggi, Palermo, 1996. Silvano Barraja's book reports also the text of many laws and decrees regulating the manufacture and trade of gold and silver items in Italy from 1872 to present days).

(3) see F. Rapposelli, Repertorio degli orefici mantovani. Maestri, botteghe e punzoni dal XVII al XIX secolo, in d’Oro e d’Argento, Castel Goffredo 2006, p. 178

(4) see F. Negrini, Servizio di posate, in d’Oro e d’Argento, Castel Goffredo 2006, p. 142