Talk:Purebreeders Society/@comment-107.160.4.171-20200804135819/@comment-38439752-20200804154820

Have a t3 of each breed, so that you can do the Horse ID tasks that give you 10 of the rarest jewel needed for the certificate. Run steeplechases whenever there are milestones to reach, since that'll help in collecting jewels as well. Fulfill the Wrangler's requests (the blue diamond icon on the map). If you have any extra dream jewels, bet those on the Fantasy Wheel (the purple unicorn icon on the map) for a chance to get common jewels (check the amount to bet for each jewel here: Fantasy Wheel (link)) Remember to set the mine and mini-mine in Germany to collect the gems you need the most as often as possible.

If you are still missing a few jewels for any certificate when the week is coming to an end, use diamonds to make up for the rest. For emeralds and sapphires it may be cheaper to skip the time on the tasks than it is to buy the jewels directly, so skip time. Rubies are so cheap at 15 diamonds each that it's pretty much always cheaper to just buy those than do anything else.

More info about the common jewels and how to earn them: Common Jewels (link).