Today marks a new chapter for Elder Scrolls Online and the new update brings a lot of changes and opportunities!
Most important for us traders is the introduction of the new jewelry crafting system. With it comes a whole slew of new materials which will open a whole new market. The new crafting materials are broken up into raw materials and refined materials like other crafts, but unlike for other crafts, the boosters and trait materials will also feature raw and refined items.
The base materials are found at new crafting nodes that share their spawn location with blacksmithing nodes and the raw boosters are gained from refining. In addition any jewelry found after the release of Summerset can be deconstructed for a chance to receive the materials. This news post on the official website explains the system in more detail.
There are also two new alchemy reagents, which will further diversify the types of potions that can be crafted. These can be obtained by opening giant clams, found along the shores of Summerset or while fishing in the that zone.
We will see some new motifs, some of which are exclusive to Summerset, but can be sold in stores. Psijic style chapters can be obtained by completing many different activites in Summerset, like clearing Abyssal Geysers or Pools, killing world and delve bosses or opening treasure chests. The Sapiarch style is available from daily quests for the Divine Prosecution in Alinor and the Pyandonean (Maomer) style can be found while fishing in Summerset. The Scalecaller and Fang Lair styles will be dropped either from the final bosses in their respective dungeon, or from the first reward chests obtained by queuing for battlegrounds. But keep in mind that the chapters dropped from the battlegrounds are bound to your account and cannot be sold.
In addition to these new motifs, there are now also "Psijic Portals" found all over Tamriel - for owners of Summerset - which have a chance to drop a motif chapter for one of the motifs of the zone. For example Apostle style chapters from portals found in Clockwork City. These portals share their spawn location with enchanting rune nodes.
Last but not least, there are also several new collectibles which can be sold to others. Cyrodiil will offer new daily quests which will reward a "Gladiator's Proof". 20 of them can be used to purchase a Gladiator's Recognition Runebox, which contains an Arena Gladiator helmet costume piece and can be sold to other players. More about the changes to Cyrodiil can be found in this news post. Aside from that there are also two new rune boxes - each in seven pieces - found in the two new public dungeons on Summerset.
Another important change for trading guilds is that there are now 13 new guild kiosks located in all major settlements in Summerset. Six are found in Alinor, one in the Alinor Outlaws Refuge and three each in Lillandril and Shimmerene.
You can read about all of the changes in the patch notes on the official forum.