The short version, for the year you came here for: 1 paper, 2 cotton, 3 leather, 4 flowers or fruit, 5 wood, 10 tin, 20 china, 25 silver, 30 pearl, 40 ruby, 50 gold, 60 diamond, 70 platinum.
For what to give in each year, rather than the material, see anniversary gifts by year.
That's the British list. If the list you have been given says something different, it is probably American or it is the "modern" one, and the difference is explained below.
The years the British list covers
Debrett's gives a material for every year up to fifteen, and then jumps: 20, 25, 30, 35, 40, 45, 50, 55, 60 and 70.
The first fifteen run paper, cotton, leather, flowers or fruit, wood, sugar, wool or copper, bronze or pottery, willow or pottery, tin, steel, silk or linen, lace, ivory, crystal. Several of those years carry two materials as alternatives rather than one replacing the other.
After fifteen it is china at 20, silver at 25, pearl at 30, coral at 35, ruby at 40, sapphire at 45, gold at 50, emerald at 55, diamond at 60 and platinum at 70.
Note what is missing: there is no material for the 65th on the British list, even though the 65th is one of the anniversaries GOV.UK names as qualifying for a message from the King.
The three things that trip people up
Your list may not match. There is a British traditional list, a modern list added in the twentieth century, and an American one, and they disagree from year two onwards. This page gives the British list as Debrett's has it. Where the sources conflict and why, is set out on the full UK anniversary list.
One year you cannot legally act on. The fourteenth is ivory, and dealing in ivory is banned in the UK bar narrow registered exemptions. Give the colour, not the material.
The gaps are real. After fifteen the list only gives the fives, and not even all of those - there is no British material for the 65th. What to do about the 65th.
Debrett's calls the list "merely a suggestion, not a prescriptive set of instructions", which is the right posture. If you want a year answered in one screen, use the free anniversary lookup; if you want the argument behind the list, read the full UK anniversary list.
