How to progress farming Amalgamated Gemstones: As you know, Amalgamated Gemstones are created by forging 3 T6 orbs/crests + 3 T6 orbs/crests + 3 T6 orbs/crests + Crystalline Dust. Now, if you're a casual like me and log in just to play 30 minutes without worrying about timers, I can help you out.
- Gathering: The best way to get orbs is gathering every T6 node (orichalcum and ancient wood) in your sight. You can either follow a route or just mine/chop whatever you find in the HoT maps and Orr. This is boring if you repeat it again and again, but just try to make it a habit to get the resources in the HoT maps. I see all the time people rushing from place to place without basically getting free in-game gold.
- Jumping Puzzles: That's right, I said it. Some of the chests from Jumping Puzzles award T6 orbs and rare crests, so if you enjoy them, you can do a different one every day. I don't follow this route though because it's too time-consuming for me for little reward (and RNG).
- Strongboxes: The best method and the one I follow every day. I don't feel it's monotonous because it's basically exploring and I enjoy that. Some of them are a bit of a Jumping Puzzle, but I usually ignore those (too time-consuming or some of them are just inaccessible because of contested waypoints). These strongboxes and chests award T6 orbs, rare crests, map currency (1-3 or 26!), some greens/rares/exotics and some special items (reclaimed weapons which sell for 8g each more or less, black diamonds and freshwater pearls which sell for 5g each). Honestly, I don't know why people don't go for these. They're "easy" to access, they don't require timers and they are quite rewarding (always with an RNG component, this is Anet after all). Fun fact, I looted a DAWN from a VB strongbox today (it's pretty uncommon I'd say, since I get 1 exotic from like 200 chests, but it can happen, so yay!)
- Mystic Forge: Here's a secret most of you don't know. If you put 4 t5 crystals or medallions (correct, the green ones you get aaaaall the time from chests/strongboxes and from rewards), there's a high chance of getting a t6 orb/crest. The probability is around 20%, I'd say, according to my forge data (I haven't abused the market because I play for myself) of around 2000 forges. It's boring because we don't have repeatable forges (YET. Please Anet...) but it's a constant progress. Every time you see you have crystals or medallions in your inventory, forge them! The same way you forge rare sigils in the chance of getting a superior sigil. It's funny because it's WAY more profitable to do this with crystals/medallions, since every outcome is positive for you! (since you're going to forge them anyway for the amalgamated gemstone). Yet people don't do it on a daily basis, maybe because they don't know it, or maybe because it's too boring doing it again and again.
- Jeweler Crystal Promotion: You know this method. You use your jeweler to upgrade t5 crystals to orbs via 5 incandescent dust. However, dust is not so easy to come by at the rate you'd need. Even then, use the dust you have! For people who spend a lot of time in the game, you can use the /wiki to learn where to farm dust (from a casual guild AC run, t5 bags from wvw...) As you can see, I use different methods because I enjoy doing different things every day, since I'm the filthiest casual.
DISCLAIMER: This is not a post to make money. You can try to make money buying medallions from the TP (2silver each, some people have been noticing about the forging that is not stated in the wiki) since the rate of upgrading is around 20% (or more, but I can't claim a percentage) and it's VERY profitable to do so, but it is so boring to forge again and again that I don't think it's worth it to dedicate your time to do this. This is more helpful for people that have medallions and crystals in their inventories and don't know that they can turn them into something useful (WITHOUT THE EXPENSIVE INCANDESCENT DUST). Thus, I hope this helps anyone who is trying to progress in their HoT legendary journey. Now all there is to do is wait for more legendaries... Anet please ;D