Nothing in particular from the "D" box to jump to immediately and highlight, so we'll just work our way through it.
Examples of interest presented in the first photo include Doyle's Mint; dhf, David H. Fell Company, Inc., Commerce City, CA; DMS, Drew Refining Company, Berkley, CA; and DGSE, Dallas Gold & Silver Exchange, Dallas, TX.
We've looked at the Doyle's Mint before in conjunction with the Coin Shack example. David H. Fell Company, Inc. began in 1973 and thrived during the 70's when most smelting and refining companies were failing. Dallas Gold & Silver Exchange is celebrating their 35th anniversary this year so while the extruded bar only dates back to the late 70's, the uniqueness of this example is that all others I have seen are overstamps of other hallmarks; this represents DGSE as a stand-alone.
On to the next photo, Doral with some of the neatest cooling rings I have ever seen.
And finally for this post, a Desert Refining International, Inc. old school finger style ingot recently acquired from one of Fred's auctions.
More to come from the D box, as always let me know if anyone has comments to share.