1. Rare: The output of silver inlaid topaz in Nepal is less. Because of its unique origin and growth environment, it is very rare, so the price is more expensive than ordinary topaz.
2. Quality: Nepal's topaz inlaid with silver usually has high transparency and less internal inclusions, so its quality is better than ordinary topaz, and its price is correspondingly higher.
3. Craft: Nepal's silver-inlaid topaz usually adopts exquisite hand-inlaid craft, which perfectly combines silver and topaz to form a unique artwork, so the price is higher than that of ordinary topaz.
To sum up, Nepal's silver inlaid topaz is expensive because of its rarity, high quality and exquisite craftsmanship. At the same time, the price is also affected by market supply and demand, fashion trends and other factors.