No one knows when traditional wedding anniversary celebrations started.
One of the most commonly quoted stories is that they date back to the Roman Empire. Husbands gave their wives silver wreaths on their 25th anniversary, and gold ones on their 50th. Other sources suggest that the same custom originates from medieval Central Europe. Even today, in many parts of the world only major milestones have traditional wedding anniversary gift associations.
Roman husbands gave their wives silver wreaths on their 25th anniversary
The Victorians, with their love of innovation and organization, felt a need to fill in the gaps. For example, when Queen Victoria celebrated her Diamond Jubilee on the 60th anniversary of her accession to the throne, people quickly adopted the material and milestone for their wedding anniversaries as well.
Diamond is the traditional 60th anniversary gift
In 1922, Emily Post, an American author, published a list of anniversary gifts in her book Etiquette in Society, in Business, in Politics, and at Home. In that she wrote a wedding anniversary gift guide that covered every fifth year of marriage up to the 25th, plus the 50th and 75th anniversaries.
The American National Retail Jewelers’ Association further expanded the list in 1937. They added materials for every year up to the 15th wedding anniversary, and for every fifth year up to the 75th. Coincidentally, many of the new materials introduced happened to be gemstones.
Emerald is the traditional 55th anniversary gift
Here's the full list of traditional anniversary gifts:
1st anniversary - paper
2nd anniversary - cotton
3rd anniversary - leather
4th anniversary - fruit/flowers
5th anniversary - wood
6th anniversary - iron
7th anniversary - copper / wool
8th anniversary - bronze
9th anniversary - pottery / willow
10th anniversary - tin
11th anniversary - steel
12th anniversary - silk / fine linen
13th anniversary - lace
14th anniversary - ivory
15th anniversary - crystal
20th anniversary - china
25th anniversary - silver
30th anniversary - pearl
35th anniversary - coral/jade
40th anniversary - ruby
45th anniversary - sapphire
50th anniversary - gold
55th anniversary - emerald
60th anniversary - diamond
65th anniversary - blue sapphire
70th anniversary - platinum
75th anniversary - diamond
80th anniversary - oak
85th anniversary - wine
90th anniversary - granite