These are beautiful medals, but they are much more works of art than coin-like medals. Appraisal by an art appraiser would be much more appropriate than this CoinQuest web site.
We will, however, tell you what we understand about these medals:
1. If you have a complete set, with all 12 tribes, it is typically worth more than 12 times the individual values. Complete sets are hard to find.
2. The medals were produced in bronze, silver, and gold.
3. They were produced between 1968 and 1996 in Israel, and notably in 1973, the 25th anniversary of Israel. The date produced is important to the value.
4. World renowned numismatists Ira and Larry Goldberg are well-versed in these medals. It would be a good idea to contact them and ask about values. Our picture comes from Goldbergs, and CoinQuest, as always, is very grateful for their permission to use their images.
5. The preponderance of value for these medals comes from the emotional connection many people have with the artist (Dali lived from 1904 to 1989). Evaluating emotional value is basically impossible, and only broad guidance can be given.
6. Values of gold and silver medals start with the value of the precious metal. They can never be worth less than that.
Please contact Goldbergs as we have suggested. A single basic bronze medal sells for roughly $30 to $50 US dollars, and a full, number-consistent set of bronze medals for $500 to $800 retail. A dealer would probably pay several $100 less than the set retail price if he or she bought one from the general public.
Silver medals are less common than bronze medals, and they contain precious metal, so their prices are higher.
Gold medals were only produced in 1968 (I believe) and are very valuable.