[colin henshaw]

Originally Posted by mariusgmioc

There are many factors to be taken into consideration when estimating the date:

1. Style - for every weapon the overall style (style = size + shape + general decorations) eveolved throughout the history (like for example during the end of Muromachi period, the size of the Japanese Katana decreased to adapt to a new figting style - with one hand - that was in fashion at that time; also the way the sword was worn changed from the Tachi type where the sword was hung edge down from the waist to the Uchigatana style with the sword worn edge up stuck in the obi);

2. Decorations - like with style, the shapes and symbols used in decorating an item evolved constantly, being strongly influenced by various historical events (for example when the Ottoman empire was at its peak, one could find decorations simiar to the Turkish ones throughout much of the Arab Peninsula and North of Africa);

3. Materials - materials used in the manufacturing of blades can be an important indicator of their age (for example, one can safely assume a Khanjar with a wootz blade must be older than the begining of 19th century, since wootz production stopped about that time);

4. Workmanship - with the passage of time new tools and new techniques were developed and that can provide major indications about the age of a blade (if for example the grooves on a blade were not chiseled by hand but machined with a rotating tool);

5. Aging signs - like rust, oxidation, patina, cracks, wear and the like, are all important age indicators for a piece (for example ivory tends to develop a darker patina and cracks with the passage of time).

A good and informative post