*** First, and foremost, the appearance of Escarchas is always unexpeted and unpredictable... they can't be "willed" or prayed to appear, but rather, it's all up to God and His divine will as to when and where they manifest. From what I've seen, this unique form of Manna appears in varying numbers primarily when there is an atmosphere of deep Christian faith and spirituality: during times of personal or group prayer (especially during the Holy Rosary); quiet spiritual reflection; and during and after Holy Mass (especially during the priest's homily, but I've never seen them materializing during the Consecration).
As far as where they appear, I've witnessed their materialization in my bedroom, at my job, in churches, and even in my car when I've driven to Mass or to prayer events where my pilgrim statue and/or relics were invited. At these places the Escarchas have manifested on a few of my statues and reliquaries (under the glass covering!), in my palms, on the faces and arms of a couple of friends, as well as on everyday items such as clothing, blankets, and even on my paperwork at my job.
*** The Escarchas first appeared as silver and golden flakes, but as weeks went by other colors have manifested, too: green, red, pink, purple, and various shades of blue. On a few occasions, the Escarchas were even colorless, resembling very small slivers of clear glass. There are a couple of websites that report the colors signify certain meanings, but I haven't experienced anything to the effect that confirmed that theory. I did notice, however, that the gold and silver Escarchas frequently appeared during Mass.
*** The Escarchas ranged in size and shape from very fine dust-like flakes to larger hexagonal particles; on one occasion, an Escarcha even took the form of a bright red heart, which caught me by surprise and touched me deeply! Stranger still, at two other times, they materialized in the form of crystalline particles resembling very tiny bits of "rock salt" (there was nothing around me that remotely resembled salt), recalling to mind the significance of salt in Sacred Scripture.
With the mention of the colorless and crystal-like forms, I also want to add that although Escarchas have often been described as "glitter", they are not - there are clear differences in size, shape, and texture from man-made glitter. In fact, the sense I've gotten is that Escarchas are organic (natural) in composition rather than synthetic (artificial).
*** The Escarchas always appeared preceded by a small, but very bright "sparkle" of light...to best describe how they appear, my immediate vicinity could be clear of any type of small debris, when suddenly, a little sparkle of white or colored light (like a tiny star!) will appear out of nowhere only to be replaced by an Escarcha. I have never seen them falling or "raining" down as described by witnesses on other religious websites.
After having collected many of the Escarchas with scotch tape, I noticed that they seem to maintain and emit their own "luminosity" rather than reflecting light from another source... and their vivid colors appear to be enhanced by the light that shines from them, which are often the same color as the Escarchas themselves.
*** The Escarchas, at times, have changed from one color to another. For example, on one occasion while I was at Mass, an Escarcha manifested near my foot. I picked-up the glittery flake with a finger and clearly saw that it was silver in color, and I rubbed it into a crease in my palm as a way of safekeeping it until I could collect it with tape. Later, when I opened my hand, I noticed that the same Escarcha had turned bright gold! At least one other person who I shared a few Escarchas with has reported back to me about its color-changing properties.
*** Lastly, the Escarchas have sometimes mysteriously multiplied, and likewise, disappeared. On several occasions, I've seen a single flake materialize on the surface of something, and after I collected it with a piece of tape, there would suddenly be other Escarchas on the same item or on my fingers! A few friends with whom I have shared some of the Escarchas with have reported how the glittery particles have later manifested on, or around them, during their personal prayer times, which could also be interpreted as a form of multiplication.
On the opposite end of the spectrum, I've seen Escarchas materialize only to vanish as mysteriously as they appeared. More than once, I've put my finger on an Escarcha in order to place it on a piece of tape, but when I looked at my finger, the Escarcha was no where to be seen.
I have to admit that I'm still baffled as to why this is all happening to me and to my friends. One website that I researched stated that Escarchas are a special sign of the Blessed Mother's presence, or even the Holy Spirit. I believe the statement is, for the most part, true... and in my experiences I feel strongly that they are connected to the Rosa Mystica Devotion, which I promote. But I certainly don't claim to be some sort of mystic, nor do I feel particularly worthy of having Our Lady or the Holy Spirit bless me in such a wondrous manner.
What I do know for sure is that I each time I witnessed the appearance of Escarchas, I feel a deep conviction in my soul that God exists and He's very, very close to us;not distant and beyond reach as some people may imagine... and He loves us very much and desires us to know it and sense it tangibly. At the same time, I feel inspired to love God in a deeper manner and my heart is filled with profound joy and gratitude.
I think a dear friend inadvertently hinted on the purpose of Escarchas when she once made a comment to me after I shared a few gold and green Escarchas with her. In a tone tinged with emotion, she told me that it was truly "dust from Heaven"... and that if the mere dust from Heaven could be so "beautiful", she can hardly wait to see the rest of God's Kingdom. It was at that point that I came to realize that through the grace of the Escarchas, Jesus was generously giving us a little "sample" of the wonder and glory of his Kingdom and the reward that awaits all of us who believe in Him and remain faithful. My faith has definitely grown and I, too, am excitedly looking forward to the day when I will finally get to see the full splendor of Heaven in person - what a sight that will be! Hallelujah... Hallelujah... Hallelujah!