The upper tier gems are very desirable items to obtain for top tier players.
Is it worth it to combine gems in the lower tiers to build up to them (obviously upper tier gems must be combined or purchased)?
Is there a certain break point where it isn't worthwhile to combine gems below that quality?
Worded differently, what price must the auction house demand for a gem before it is not worth combining them yourself?
As stated here, the new costs in the 1.0.3 patch deployed on June 19 are:
Quality Previous Cost New Cost
Flawed 3 Chipped + 500 gold 2 Chipped + 10 gold
Normal 3 Flawed + 750 gold 2 Flawed + 25 gold
Flawless 3 Normal + 1250 gold 2 Normal + 40 gold
Perfect 3 Flawless + 2000 gold + 1 Page 2 Flawless + 55 gold + 1 Page
Radiant 3 Perfect + 3500 gold + 2 Pages 2 Perfect + 70 gold + 2 Pages
Square 3 Radiant + 7500 gold + 1 Tome 2 Radiant + 85 gold + 1 Tome
Flawless Sq. 3 Square + 20,000 gold + 2 Tomes 2 square + 100 gold + 2 Tomes
For example, to upgrade from chipped to flawless square:
1 Flawless Square
= 2 square + 100 gold + 2 tomes
= 2 * (2 Radiant + 85 gold + 1 tome) + 100 gold + 2 tomes
= 4 * ( 2 Perfect + 70 gold + 2 pages ) + 270 gold + 4 tomes
= 8 * ( 2 Flawless + 55 gold + 1 page ) + 550 gold + 8 pages + 4 tomes
= 16 * ( 2 Normal + 40 gold ) + 990 gold + 16 pages + 4 tomes
= 32 * ( 2 Flawed + 25 gold ) + 1630 gold + 16 pages + 4 tomes
= 64 * ( 2 Chipped + 10 gold ) + 2430 gold + 16 pages + 4 tomes
= 128 Chipped + 3070 gold + 16 pages + 4 tomes
Assume drop rates are going to remain unchanged and thus the prices of pages and tomes should be relatively stable (this assumption may be invalid, explain why if you disagree).
At what price for a flawless square does it become worth taking a DIY approach?