@4krowme -
You're welcome.
I've encountered solders, whose flux chemistry made the finished product look, "dull". Flux removal brought out the shine.
There are other, more compelling reasons for flux removal, than aesthetics, of course*.
*Good stuff, here: https://www.chemtronics.com/do-you-need-to-clean-flux
Then again: I have seen cold solder joints that appeared dull, without the other signs/visuals, that would indicate a faulty joint. That makes the case for an iron and large enough tip, to maintain a recommended temp, as well as sufficient/proper application of the heat (time, tinning and tip position.
Regarding a good, silver-bearing solder: as mentioned: https://www.amazon.com/Cardas-Soldering-Eutectic-Silver-Solder/dp/B015X68HXW
Adhere to their temp recommendations, follow good soldering guidelines and you can't go wrong!
Happy holidays and hobbying!