Crystaline pattern on poured bars

Why do I get this crystalline pattern? It only occurs when I'm pouring high purity silver. It does not happen when pouring Sterling bars or 990 bars. The pattern is somewhat exaggerated on the top photo because I soaked it overnight in a 10% H2So4 solution. These are 5 and 3 ounce bars. The 5 ounce bar was poured this morning and it was from cemented mud. The smaller bar was poured from crystals from my cell. The bars are smooth on top and sometimes have a wavy pattern visible in the silver which can be seen but not felt. I have poured over 100 high purity bars and they have all had this pattern on top and sometimes on the sides but rarely on the bottom. A quick burnish with “0000” steel wool causes it to disappear and the bars polish to the normal high silver luster with no crystalline pattern visible. Both these bars were poured using my copper buss bar mold. This mold or my graphite mold makes no difference as far as this crystalline pattern is concerned. Mike

Are you preheating your molds?

Why would you not want that? My customers pay good money when i sell bars like that. Usually around 125% of spot.

Palladium said:

Why would you not want that? My customers pay good money when i sell bars like that. Usually around 125% of spot.

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I agree with Palladium.... I'd like to learn your process so I can get some bars looking like that.

Barren Realms 007 said:

Are you preheating your molds?

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Only very lightly. With the copper buss mold I have found that applying my torch to it for about 5 seconds gives the best results.

Mike

Palladium said:

Why would you not want that? My customers pay good money when i sell bars like that. Usually around 125% of spot.

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So I take it that you have poured bars like that? You're the first that has said that, that I have noticed. I thought I was doing something wrong.

Mike

Hell no brother those bars look great! That's tells you that you have high purity. I love to do gold that way. Look at the top of these bars and notice the foil effect.

Back in nov 2010 I had my first expirience with the crystal. I used a 3.4 Toz gold bar to get rid of some nitric and this was the result.
I've also done it with silver.
Phil

I have noticed that the quicker the metal solidifies, the more pronounced the pattern of molecule alignment is and it doesn't or hasn't so far mattered what metal I pour, even had aluminum that was just as pronounced as your silver bars.

Smack said:

I have noticed that the quicker the metal cools, the more pronounced the pattern of molecule alignment is and it doesn't or hasn't so far mattered what metal I pour, even had aluminum that was just as pronounced as your silver bars.

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That's odd because I get the more pronounced crystal patterns on the bigger bars which take longer to cool. Also, I forgot the one 18 gram bar I poured (1/2" x 1" x 1/8" thick) from some left over cell crystals. That one cooled very quick and did not have the crystal pattern.

Mike

I meant to say solidifies Mike. The quenching might have something to do with it also.

Palladium said:

Why would you not want that? My customers pay good money when i sell bars like that. Usually around 125% of spot.

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I haven't got the nerve to do gold yet. I'm afraid of making a mistake and loosing any small margin I may have gotten.
Mike

The crystalline formation is throughout the bars, not just on the surface. I ran some bars through my silver cel that had this pattern on them and about hlfway through their ingestion i noticed that iswas not just a surface effect. Palladium is rigt though, they do sell above spot. This was discussed a while back andit was said you get thi ffect with high purity metals, .9999+ if i remember correctly. Good work brother!

Lou




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August 11th, 2012, 9:34 pm

Re: so happy with my latest silver bar. Thank you Lou and St

Nice, looks good. What does the flux look like? It should be only the slightest creme color (just slightly yellow and off white) if the silver is over 3N5. Usually you will see crystals on the surface if it is 3N5+. On 4N-5N+ silver, they will be half cm or larger planes and iridescent and your silver bar will have a weird holographic look to it.

its-all-a-lie said:

Nice, looks good. What does the flux look like? It should be only the slightest creme color (just slightly yellow and off white) if the silver is over 3N5. Usually you will see crystals on the surface if it is 3N5+. On 4N-5N+ silver, they will be half cm or larger planes and iridescent and your silver bar will have a weird holographic look to it.

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The bottom of the crucible is the color of cream from a Jersey cow. (I grew up on a dairy)

Mike

Showes good purity, 3N5+.

Nice looking bars Mike.

I did another batch today. The first cement harvest resulted in bars with the crystal pattern and the bar from the last harvest did not show the pattern. Matter of fact, the last cement harvested produced more black mud than usual. I found a way to separate it to a degree. It was heaver so I was able to use the plastic bucket kind of like a gold pan and separate the grey mud from the black mud with help from my spray bottle. More got caught in the filter. I dryed it and tested it with my Platinum test solution and it did turn orange. Mike

Try some lotion on those dried out hands.

Might help. :lol:

Ocean said:

Try some lotion on those dried out hands.

Might help. :lol:

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50 years younger would help more! 8)

Mike your hands look like mine, well worked.