As to hunting in Pattern 2...... some of the finds that I've made with my X-TERRA, that I wouldn't have using Pattern 2 include a US 3-cent nickel, a US 3-cent Silver, several old Indian cents that read as low as 24, at least a half dozen small gold rings that read 4 or 6. Don't get hung up on using preset Patterns. All Patterns are easily adjusted by simply pressing the accept/reject pad for that TID number.
As to not finding silver..........The US stopped minting silver coins in the US in 1964. Many of us started detecting around that time, or shortly thereafter. The detectors we had then were not good discriminators, so we dug pretty much everything that beeped. We hunted parks, yards, school grounds, church yards and just about everywhere else you can imagine. Frankly, it didn't take as much imagination to find a "good spot" then, as it does today. So here we are, 46 years after the last silver coins were minted. And people have continued detecting, even with no silver being minted. And many of them are hunting the same parks, yards, schoold grounds, church yards that we've been hunting for over 40 years. To find silver today, it takes research, patience and perserverance. And a little luck now and then don't hurt either.
With all things being equal, a silver coin will read the same as a clad coin of equal value. But if you look at the coin chart in the FAQFAQ section, you will see that all coins are not created equal. Again, I've hit IH cents as low as 24 and as high as 34. I've dug silver dimes that read a 36, some at 38 and others at a 40. If you don't want to take the time to go through the FAQFAQ section, here is a link to that US coin chart. http://www.findmall.com/read.php?55,1130228,1130230#msg-1130230
The 99 tones you referred to is actually 28 tones. That represents one tone for each of the 28 notch segments. Therefore, if a target has a TID value of 36, it will produce the tone assigned to notch segment 36. No matter if it is a silver dime, a large gold ring, an old $20 gold piece, a wheat penny or a screw cap...... if it says 36, it will produce the tone associated with 36. There are some subtle differences in the "harmonics" that you will hear if you are using less rejection. But for the most part, clad dimes will sound just like silver dimes.
Keep at it. If you're finding clad, you're doing something right. Just a matter of getting your coil over the silver! HH Randy