No stocks can ever really be compared apples to apples and ASN/PNN are no exception, there are way too many other variables to even try to consider a comparison.
Regardless of the initial reason people have invested in ASN, the credits from additional resources I believe will assist to make this a viable project.
Lets imagine (speculate) that the Lithium price drops over the next few years as Macquarie have forecast (I think Mac have it wrong anyway but that's a whole different story), ASN also having Bromine & Iodine may just be slightly future proof (or further de-risked) because of the additional minerals, which may enable the project to remain operational, whereas under the same conditions there would more than likely be several smaller prospectors & even miners/producers who will have to go to care and maintenance or at very least tighten their operations to remain profitable. The investment risk for those that are in the early stages of development has increased substantially due to the Macquarie comments, resulting in lower or even discounted share prices.
Both stocks were clearly pumped during the later part of last year and the extent of the rise and fall is partially dependent on the amount of accumulation prior to the pump, as well as market sentiment and the ongoing volume during the peaks enabling the price to hold up. Some pumps are just that ,a pump, driven by hype, little more, whereas others may have some component of a pump but the percentage of fundamental investors is much higher, these investors tend to hang on longer and aren't just there for the short term profit, I'm guessing, by volume alone, that this is the case with ASN.
To try to put things into perspective which is near on impossible:
PNN increased some 500-600+% over the period of the bull cycle (A lot of average punters would have probably only rode it from the 0.03 point after the hype started to flow. In addition I believe PNN would have had quite a few stale holders from between 0.02 & 0.04 who would have jumped at the opportunity to bail early. PNN has now fallen approx 70% from it's end of year high, although is still up almost 100% from it's pre bull cycle pump. Whether or not PNN is oversold is not something I would comment on but technicals suggest to me that it is, but also that it will continue to fall until it reaches a base which looks to be around .023 atm. PNN currently have approx 527M shares, 42% held by the top 20 and market cap of around $14M & reached up near $50M at its peak. Prior to the pump the MC was around $8M.
ASN on the other hand rose somewhere between 500 & 3000% to 0.30. To be fair I would put it at 500 to 1000% taken from after the first leg up where it reached approx 0.030 and took in a lot of volume at this time (around end of September), as well as during the period at about 0.05, although it was down as low as 0.010 just prior to this but there was not a great deal of volume. ASN has fallen over 80% from it's high, although it is also currently still up approx 300% from it's low prior to the pump. It currently has approx 411M shares and market cap of around $24M and reached up near $150M at its peak, approx 37% of total shares are held by the top 20. Prior to the pump the MC was around $4-5M. Whether or not the $150M M/C was justified is disputable but I would say it was over bought, especially once the Lithium forecast and associated sentiment changed across the market as a whole.
From the above we can see that PNN was of lower value than ASN prior to the bull run but ASN pumped a lot harder with a lot higher & consistent volume. As an example ASN had a daily volume of 381M at its peak whereas PNN's maximum daily volume was 100M and that was back in March (remember those stale holders), the largest volume day was 61M shares during the main bull run. ASN actually have less tradeable shares on offer although had a greater volume, basically ASN has had a much larger turnover, and a lot of fresh holders who may just be sitting tight waiting for the story to unfold. Whether or not ASN current MC of $24M or PNN's market cap of $14M are justifed is really anyones guess and the market has guessed that ASN is indeed worth it's $24M and that PNN is not. And the market is always right, regardless of what any one person thinks, the collective says it is so and so be it.
One last thing, at the time of the last quarterly PNN also only had $1m in bank and forecast 700k spend for the qtr just gone leaving only $300k up to end of March 2018. ASN were at $3.2M in bank with a forecast spend of approx $1m, leaving $2.2M in bank. ASN appear to be controlling cost better than PNN in my opinion.
The above hasn't even touched on fundamentals/ complete resource values, strategic investors, Top 20 holders, previous history or management actions and is only basic research and a small part of the picture (I haven't even looked at PNN in depth at all).
As much as any two companies may look the same they are way different animals and at the end of the day the price is driven mainly by sentiment at this end of the market.
P.S. On your comment re ppm 180 Versus 142, does it mean that much really? At only about 26% greater concentration, the quantity of available resource/fluid/brine at that concentration may be much higher than PNN and the recoverable Lio2Co3 may be greater and cheaper to process.
Then there's this to throw a spanner in the works,
(20min delay)