Many people asked me about LP Thuat (nur wahn) of 2497 and 2505 origin. What is the difference, how many type , material composition, how to differentiate etc.
I would like to pen down what i know and my advice as well.
For 2497, it was well know for the fact that it was the first LP Thuat image. Ajarn Tim the then abbot of Wat Changhai, get "authorized" by LP Thuat to make this images to bless the devotees. It was made of mixture of both "earth" and "herbs". The colour of the amulets depends on material composition and mixture. The more "earth" it is the darker it became and the more herbs it has, the amulet appears brownish or greyish.
Almost all monk stayed near Wat Changhai participated in the making of LP Thuat. The younger monks helped to make materials into "nur" whereas the older/ more senior monks helped to pray/chant. Many special steps were needed to create herbal amulet by hand. Each Nur is unique due to different percentage of ingredients, different time taken to mix/press into mold and dry time too. Nur was sculpted into hundreds of "ball" and hand-pressed them into mold and let it dry naturally. The one that are left to be pressed later, was mostly dried off and cracked easily. Nur that was not "elastic" enough, resulted in crack. Nur that was too liquid will not produce sharp edges and accurate features. The final piece looks all different because of all these factors despite being mixed with the same ingredient. That is the reason why it is hard to find 2 identical pieces and it is so difficult to authenticate a 2497 even for expert in LPT.
So, to authenticate, please make sure you check the form, the ingredient, greasiness, dryness of materials. If possible, scrap a bit and go through spectrometric analysis to see exact composition and age of the materials. :)
It is that difficult. Strangely, some 2497 are easier to be authenticated than others. And those easier to be authenticated, are usually those that are in bad form. Super dry and the right composition visibly seen. They are cheaper too (due to its bad condition or worn out condition) but safer in my opinion.