Gold Isnt Going Into Solution. Help?

[Crank]

I'm currently in the process of trying to dissolve my gold foils in aqua regia. I started with 400 ml 31.35% HCl and I incrementally added 67% nitric until I saw foils beginning to dissolve. I've had the solution on a medium boil for about 25 minutes. It appears that the solids have dissolved so I did a stannous test. The fluid is a nice yellow color on the paper but when I drop the stannous on, there is no change.
Do I keep it on heat and wait longer? Add more nitric?

 

[Crank]

The photo of the opaque container is to give you folks an idea of what the foils look like.

 

[Crank]

Update- I pressed on with the AR processing on heat for about 45 minutes. I pulled it from heat and cooled it down with ice. I ran it through a filter and dropped the solution with SMB. 30 minutes later, I had a beaker with a lovely layer of mud at the bottom.
I dried the mud and melted it down into my first button. 4.75g!

I must be doing something wrong with my stannous test. I have to see if I can figure out what I am missing in that test.

 

[eaglekeeper]

How did you make your stannous solution.

Next time you decide to do some more foils, isolate a pinch of the clean foils. Then dissolve them and store solution in a small bottle. That way you can have a gold standard test solution to test your stannous,

 

[Crank]

I didn't make it. I purchased a bottle through a vendor linked through this site. I picked up the bottle out of convenience as I had other chemicals I needed to purchase.
I may just empty it and make my own.

 

[eaglekeeper]

Yea, who knows how long that stannous sat on the shelf before they sent it to you..

I dissolve regular old tin solder from the hardware store and filter out any solids. Or you can get pure Tin shot off amazon. I made my stannous over a year ago and it is still works good.

 

[Crank]

I'm doing that very thing too. I disposed of the old stannous and am reusing the bottle. It's full of HCl with a couple of chunks of solder that I flattened with a hammer.
I had to put my AR aside until I have stannous. I dropped the gold and poured the liquid off yesterday. The yield was good but I suspect there is still some in solution. I ran out of SMB too, as luck would have it

 

[eaglekeeper]

I'm doing that very thing too. I disposed of the old stannous and am reusing the bottle. It's full of HCl with a couple of chunks of solder that I flattened with a hammer.
I had to put my AR aside until I have stannous. I dropped the gold and poured the liquid off yesterday. The yield was good but I suspect there is still some in solution. I ran out of SMB too, as luck would have it

You may already know this, but Ace/Lowes hardware sells Bonide stump remover that's SMB. Home brewing stores sells Campden tablets that are SMB and any place that sells canning supplies has SMB.

 

[Martijn]

I disposed of the old stannous and am reusing the bottle.

How did you dispose of it, if may ask?

 

[Crank]

I've moved it to a sealed jar. I segregate chemicals and occasionally make a run to my local chemical disposal site. Generally for stuff like this I will label the bottle as 'do not use', followed by the name of the solution.