I made a tribute to Hyalites from Hungary, Zemplén, Tarcal. Specimens are shown in normal, UV-C and some in UV-A light. All frames are made from individual photos (more than 2000 were needed for the video).
Hungary has some really outstanding localities for unique hyalites: Monok, Gyöngyössolymos and recently Tarcal. Specimens from this locality tend to be the biggest, glassiest and the best from Hungary! The downside is that the andesite quarry uses explosives, which damages most opals before anyone had the chance to collect them. Plus the quarry is now closed for mineral collectors, meaning very small amount of acceptable specimens make it to the market every year (if any). Hyalites glow green in UV-C light (short wave UV light), and the white/yellow Calcite, Aragonite show medium fluorescence under UV-A light: usually bluish, yellow or white.
Specimen at 0:11
Size: 50*40*44 mm,
Thin hyalite coating andesite tuff. One of the best habits from the locality. Shown in normal light, then in UV-C (short wave UV light)
Specimen at 0:17
Size: 23*15*36 mm
Flawless 18 mm tall hyalite aggregate on andesite tuff. One of the best habits from the locality. Excellent contrast, and no damage on the specimen. Shown in normal and UV-C light.
Specimen at 0:28
Size: 20*21*24 mm,
A perfect, 20 mm hyalite crown sitting on matrix. Hyalite crowns are probably the most desired and best habits from Tarcal. Shown in normal and UV-C light.
Specimen at 0:40
Size: 20*11*38 mm,
Glassy hyalite crown sitting on minor matrix. Shown in normal and UV-C light.
Specimen at 0:47
Size: 24*24*29 mm,
Flawless 16 mm tall hyalite aggregate on andesite tuff with multiple attachment points! This is also somewhat common with specimens from Tarcal, but it is very apparent on this specimen. This specimen is also shown in normal and UV-C light.
Specimen at 0:54
Size: 21*26*35 mm,
One of my best hyalite crowns (27 mm), also sitting on andesite tuff. This was also the hardest one to take good photos of. Only shown in normal light.
Specimen at 1:00
Size: 29*22*41 mm,
Condition: very good
This habit with calcite and aragonite was most common in 2013 in the quarry. It has a little damage on the back-bottom side, but nothing noticable. The specimen is shown in UV-C, normal and in UV-A (long wave UV light).
Specimen at 1:12
Size: 91*46*35 mm,
Condition: very good
This habit with calcite was most common in 2013 in the quarry. It has a little damage on the back side, but nothing noticable. The specimen is shown in UV-C, normal and in UV-A (long wave UV light). When it starts rotating back it is shown in UV-C + UV-A light.
Gem at 1:19
Size: 3.0 ct, 9*9*7 mm
Condition: very good cut with minor inclusions.
Some hyalites are great for cutting gemstones. They might looks simular to glass in normal light, but it is a whole different story in UV-C light! If you are interested in faceted hyalite from Tarcal or Monok, please let me know!